diff --git a/crates/oxide_emit/src/capture/mod.rs b/crates/oxide_emit/src/capture/mod.rs
index 83b18bff..8538fd36 100644
--- a/crates/oxide_emit/src/capture/mod.rs
+++ b/crates/oxide_emit/src/capture/mod.rs
@@ -16,6 +16,7 @@ mod upvalues;
 use std::collections::HashSet;
 
 pub(crate) use captured::collect_captured_bindings;
+pub(crate) use names::collect_direct_lexical_names;
 pub(crate) use names::collect_own_binding_names;
 pub(crate) use names::collect_top_level_function_names;
 pub(crate) use names::collect_top_level_function_names_ordered;
diff --git a/crates/oxide_emit/src/capture/names.rs b/crates/oxide_emit/src/capture/names.rs
index b05287cf..fc51cd9d 100644
--- a/crates/oxide_emit/src/capture/names.rs
+++ b/crates/oxide_emit/src/capture/names.rs
@@ -124,6 +124,63 @@ pub(crate) fn collect_top_level_function_names_ordered(stmts: &[Statement]) -> V
     names
 }
 
+/// 收集语句列表**直接子级**词法声明名（let/const，含解构 pattern 叶）：
+/// 入口 TDZ 占位 cell 名集（被捕获的词法绑定在入口未初始化）。
+///
+/// 遍历面与 `predeclare_lexical_declarations` 一致——只走直接子级，不递归块/
+/// if/for/switch case/try 区（块级名不提升到函数/程序作用域，不建入口
+/// cell）；for 头声明是循环作用域绑定，不纳；var 声明不纳（var 入口实例化
+/// 独立覆盖）；import 绑定由模块导入初始化的发射点建 cell，不纳。
+pub(crate) fn collect_direct_lexical_names(stmts: &[Statement]) -> HashSet<String> {
+    let mut names = HashSet::new();
+    for stmt in stmts {
+        match stmt {
+            Statement::VariableDeclaration(decl) => {
+                if matches!(decl.kind, VariableDeclarationKind::Var) {
+                    continue;
+                }
+                for d in &decl.declarations {
+                    collect_binding_pattern_names(&d.id, &mut names);
+                }
+            }
+            Statement::ClassDeclaration(cd) => {
+                if let Some(id) = &cd.id {
+                    names.insert(id.name.to_string());
+                }
+            }
+            Statement::ExportNamedDeclaration(exp) => {
+                if let Some(decl) = &exp.declaration {
+                    match decl {
+                        oxide_parser::Declaration::VariableDeclaration(vd) => {
+                            if matches!(vd.kind, VariableDeclarationKind::Var) {
+                                continue;
+                            }
+                            for d in &vd.declarations {
+                                collect_binding_pattern_names(&d.id, &mut names);
+                            }
+                        }
+                        oxide_parser::Declaration::ClassDeclaration(cd) => {
+                            if let Some(id) = &cd.id {
+                                names.insert(id.name.to_string());
+                            }
+                        }
+                        _ => {}
+                    }
+                }
+            }
+            Statement::ExportDefaultDeclaration(exp) => {
+                if let oxide_parser::ExportDefaultDeclarationKind::ClassDeclaration(cd) = &exp.declaration {
+                    if let Some(id) = &cd.id {
+                        names.insert(id.name.to_string());
+                    }
+                }
+            }
+            _ => {}
+        }
+    }
+    names
+}
+
 /// 收集当前函数作用域声明的绑定名（参数 + 变量/函数声明，含嵌套 block，不含嵌套函数体）。
 pub(crate) fn collect_own_binding_names(param_names: &[&str], stmts: &[Statement]) -> HashSet<String> {
     let mut names = HashSet::new();
diff --git a/crates/oxide_emit/src/errors.rs b/crates/oxide_emit/src/errors.rs
index 6219ba1e..db72802e 100644
--- a/crates/oxide_emit/src/errors.rs
+++ b/crates/oxide_emit/src/errors.rs
@@ -47,9 +47,20 @@ impl Emitter {
     /// 赋值目标 TDZ 检查：未初始化绑定在赋值引用解析时抛 ReferenceError。
     /// 须在 RHS 求值之前调用（规范：赋值 LHS 的 ResolveBinding 先于 RHS 副作用）。
     ///
+    /// # 边界与前提
+    /// - 被捕获名（upvalue）跳过：其 TDZ 由运行时 cell 初始化标志判定，编译期
+    ///   快照对声明序晚于函数编译的绑定是陈旧的。
+    ///
     /// # 副作用
     /// - TDZ 命中时发射 THROW 指令序列，其后指令不可达但保持寄存器良定义。
     pub(crate) fn emit_identifier_tdz_guard(&self, name: &str, ctx: &mut CompileCtx) -> Result<(), String> {
+        // 被捕获绑定经运行时 cell 的初始化标志统一判定（cell 读写与 upvalue
+        // 读写同面）：嵌套函数 ctx 继承的父作用域 initialized 快照是陈旧的
+        // （函数声明编译早于 let/const 声明的初始化点），静态 throw 会误报，
+        // 命中捕获名即跳过，真 TDZ 由运行时抛。
+        if ctx.current_upvalue_captures.iter().any(|u| u.name == name) {
+            return Ok(());
+        }
         if let Some((binding, _)) = ctx.scopes.symbols.lookup_any_binding(name) {
             if !binding.initialized {
                 let _ = self.emit_tdz_throw(&format!("Cannot access '{name}' before initialization"), ctx)?;
diff --git a/crates/oxide_emit/src/function_body.rs b/crates/oxide_emit/src/function_body.rs
index 4b017026..75936072 100644
--- a/crates/oxide_emit/src/function_body.rs
+++ b/crates/oxide_emit/src/function_body.rs
@@ -14,8 +14,8 @@ use oxide_ir::IRFunction;
 use oxide_parser::{Expression, Statement, VariableDeclarationKind};
 
 use crate::capture::{
-    collect_binding_pattern_names, collect_captured_bindings, collect_own_binding_names, collect_upvalue_names,
-    collect_var_binding_names,
+    collect_binding_pattern_names, collect_captured_bindings, collect_direct_lexical_names, collect_own_binding_names,
+    collect_upvalue_names, collect_var_binding_names,
 };
 use crate::compile_ctx::{CompileCtx, FieldBuffer};
 use crate::symbol_table::{Binding, ScopeKind};
@@ -783,6 +783,33 @@ impl Emitter {
             }
         }
 
+        // 被捕获函数作用域词法（let/const/class）入口 TDZ 占位 cell：函数声明
+        // hoisting 先于声明语句执行时，闭包指向此未初始化 cell，声明前读写经
+        // 运行时抛真 TDZ；声明语句的 MAKE_CELL 按占位更新语义原位翻转。名集只取
+        // 直接子级（块级名不提升到函数作用域，与块内重执行 cell 族零交集），
+        // 排序保证发射序跨进程稳定。
+        let mut lex_names: Vec<String> = collect_direct_lexical_names(body_stmts)
+            .into_iter()
+            .filter(|n| !param_names.contains(&n.as_str()) && n != "arguments")
+            .filter(|n| ctx.captured_bindings.contains_key(n))
+            .collect();
+        lex_names.sort();
+        if !lex_names.is_empty() {
+            let undef_reg = self.emit_undefined(ctx);
+            for name in lex_names {
+                if let Some(&cell_idx) = ctx.captured_bindings.get(&name) {
+                    // 未初始化标志折入 16 位立即数高字节（0x0100），dispatch 侧
+                    // 按字节拆回两字段。
+                    ctx.inst(Inst::new(
+                        OpCode::MAKE_CELL,
+                        Operand::Reg(undef_reg),
+                        Operand::Imm(cell_idx as u16 | 0x0100),
+                        Operand::None,
+                    ));
+                }
+            }
+        }
+
         Ok(param_base)
     }
 
diff --git a/crates/oxide_emit/src/module.rs b/crates/oxide_emit/src/module.rs
index 5e402159..e1ff60bd 100644
--- a/crates/oxide_emit/src/module.rs
+++ b/crates/oxide_emit/src/module.rs
@@ -725,6 +725,31 @@ impl Emitter {
                     }
                 }
             }
+            // 被捕获模块词法（let/const/class）入口 TDZ 占位 cell：模块词法导出
+            // 既有预注册保持未初始化 TDZ（命名空间对象面，按导出名），入口 cell
+            // 只覆盖被嵌套函数捕获的名（按捕获名），两面名集独立。声明语句的
+            // MAKE_CELL 按占位更新语义原位翻转；直接子级 only，块级名不提升。
+            let mut lex_names: Vec<String> = crate::capture::collect_direct_lexical_names(body)
+                .into_iter()
+                .filter(|n| !ctx.param_names.contains(n.as_str()))
+                .filter(|n| ctx.captured_bindings.contains_key(n))
+                .collect();
+            lex_names.sort();
+            if !lex_names.is_empty() {
+                let undef_reg = self.emit_undefined(ctx);
+                for name in lex_names {
+                    if let Some(&cell_idx) = ctx.captured_bindings.get(&name) {
+                        // 未初始化标志折入 16 位立即数高字节（0x0100），dispatch 侧
+                        // 按字节拆回两字段。
+                        ctx.inst(Inst::new(
+                            OpCode::MAKE_CELL,
+                            Operand::Reg(undef_reg),
+                            Operand::Imm(cell_idx as u16 | 0x0100),
+                            Operand::None,
+                        ));
+                    }
+                }
+            }
         }
 
         // —— re-export（export { x } from 'mod'）链接检查：实例化期解析，须先于
diff --git a/crates/oxide_emit/src/program.rs b/crates/oxide_emit/src/program.rs
index bd5eac3b..a610bb2f 100644
--- a/crates/oxide_emit/src/program.rs
+++ b/crates/oxide_emit/src/program.rs
@@ -17,8 +17,8 @@ use oxide_ir::IRFunction;
 use oxide_parser::Statement;
 
 use crate::capture::{
-    collect_captured_bindings, collect_own_binding_names, collect_top_level_function_names,
-    collect_top_level_function_names_ordered, collect_var_binding_names,
+    collect_captured_bindings, collect_direct_lexical_names, collect_own_binding_names,
+    collect_top_level_function_names, collect_top_level_function_names_ordered, collect_var_binding_names,
 };
 use crate::compile_ctx::CompileCtx;
 use crate::Emitter;
@@ -377,6 +377,31 @@ impl Emitter {
             }
         }
 
+        // 被捕获顶层词法（let/const/class）入口 TDZ 占位 cell：声明语句执行前
+        // 创建的闭包指向此未初始化 cell，声明前读写经运行时抛真 TDZ；声明语句
+        // 的 MAKE_CELL 按占位更新语义原位翻转为已初始化。名集取捕获集交集
+        // （直接子级词法名，块级名不提升到顶层），排序保证发射序跨进程稳定。
+        let mut lex_names: Vec<String> = collect_direct_lexical_names(&program.body)
+            .into_iter()
+            .filter(|n| ctx.captured_bindings.contains_key(n))
+            .collect();
+        lex_names.sort();
+        if !lex_names.is_empty() {
+            let undef_reg = self.emit_undefined(&mut ctx);
+            for name in lex_names {
+                if let Some(&cell_idx) = ctx.captured_bindings.get(&name) {
+                    // 未初始化标志折入 16 位立即数高字节（0x0100），dispatch 侧
+                    // 按字节拆回两字段。
+                    ctx.inst(Inst::new(
+                        OpCode::MAKE_CELL,
+                        Operand::Reg(undef_reg),
+                        Operand::Imm(cell_idx as u16 | 0x0100),
+                        Operand::None,
+                    ));
+                }
+            }
+        }
+
         // 全局声明实例化序言：脚本求值前为顶层 var 名创建全局对象属性（值 undefined），
         // 使声明语句执行前的读取（typeof、反射、自引用）可经全局对象见绑定。
         // 顶层函数声明名不进序言：函数值是编译闭包，编译期不可得，其全局对象属性值
diff --git a/crates/oxide_vm/tests/tdz_upvalue_capture_tests.rs b/crates/oxide_vm/tests/tdz_upvalue_capture_tests.rs
new file mode 100644
index 00000000..55221b5f
--- /dev/null
+++ b/crates/oxide_vm/tests/tdz_upvalue_capture_tests.rs
@@ -0,0 +1,288 @@
+//! 被捕获词法绑定（let/const）的 TDZ 语义钉：入口 TDZ 占位 cell 与赋值引用形
+//! 静态守卫跳过的引擎侧行为锁。顶层/函数作用域的词法绑定被嵌套函数捕获后，
+//! 声明语句执行前的读写须经运行时 cell 的未初始化标志抛 ReferenceError，
+//! 声明语句执行后读写正常；const 捕获绑定的写点抛 TypeError。
+//!
+//! 完成值一律收敛为布尔（JsValue 的 Display 不暴露字符串内容），字符串比较在
+//! 引擎内完成。
+
+use std::sync::Arc;
+
+use oxide_compiler::compiler::Compiler;
+use oxide_parser::Allocator;
+use oxide_vm::vm::Vm;
+
+fn eval(source: &str) -> String {
+    let allocator = Allocator::default();
+    let program = match oxide_parser::parse(&allocator, source) {
+        Ok(p) => p,
+        Err(e) => return format!("parse error: {}", e[0].message),
+    };
+    let module = match Compiler::new().compile(&program) {
+        Ok(m) => m,
+        Err(e) => return format!("compile error: {e}"),
+    };
+    let mut vm = Vm::new();
+    match vm.run(&Arc::new(module)) {
+        Ok(result) => format!("{result}"),
+        Err(e) => format!("vm error: {e}"),
+    }
+}
+
+// ── 顶层 let 被函数声明捕获：声明后赋值引用形（编译序判别面）──
+
+#[test]
+fn captured_top_let_update_after_decl_returns_new_value() {
+    // 函数声明先于 let 声明语句编译，捕获 cell 在声明语句执行后才翻转已初始化，
+    // 赋值引用形不得误报编译期 TDZ。
+    assert_eq!(
+        eval("let step; function r() { step++; return step; } step = 0; r() === 1"),
+        "true",
+        "captured top-level let update works after the declaration executes"
+    );
+}
+
+#[test]
+fn captured_top_let_simple_assign_after_decl() {
+    assert_eq!(
+        eval("let step; function r() { step = 7; return step; } step = 0; r() === 7"),
+        "true",
+        "captured top-level let simple assignment works after the declaration executes"
+    );
+}
+
+#[test]
+fn captured_top_let_compound_assign_after_decl() {
+    assert_eq!(
+        eval("let step; function r() { step += 5; return step; } step = 1; r() === 6"),
+        "true",
+        "captured top-level let compound assignment works after the declaration executes"
+    );
+}
+
+#[test]
+fn captured_top_let_bare_read_after_decl() {
+    // 裸读不经静态守卫，守卫跳过面不得波及裸读路径。
+    assert_eq!(
+        eval("let step; function r() { return step; } step = 0; r() === 0"),
+        "true",
+        "captured top-level let bare read works after the declaration executes"
+    );
+}
+
+#[test]
+fn captured_top_let_update_in_stringify_replacer() {
+    // builtin 回调深度不影响判别：赋值引用形只由编译序决定。
+    assert_eq!(
+        eval(
+            "let step; function r() { step++; return step; } step = 0; JSON.stringify({ a: 1 }, (k, v) => { r(); return v; }); step === 2"
+        ),
+        "true",
+        "captured top-level let update works from a stringify replacer"
+    );
+}
+
+#[test]
+fn captured_top_let_update_in_map_callback() {
+    assert_eq!(
+        eval("let step; function r() { step++; return step; } step = 0; [1, 2].map(() => r()).join(',') === '1,2'"),
+        "true",
+        "captured top-level let update works from an array map callback"
+    );
+}
+
+#[test]
+fn captured_top_let_update_in_stringify_replacer_expr() {
+    assert_eq!(
+        eval("let step; function r() { step++; return step; } step = 0; JSON.stringify({ a: 1 }, (k, v) => r() || v); step === 1"),
+        "true",
+        "captured top-level let update works when the replacer is a bare call expression"
+    );
+}
+
+#[test]
+fn captured_top_let_update_in_getter() {
+    assert_eq!(
+        eval("let step; function r() { step++; return step; } step = 0; Object.values({ get a() { return r(); } }).join(',') === '1'"),
+        "true",
+        "captured top-level let update works from an object getter"
+    );
+}
+
+#[test]
+fn captured_top_let_update_in_nested_arrow() {
+    // 链式捕获（内层箭头的 upvalue 指向外层闭包的 upvalue cell）。
+    assert_eq!(
+        eval("let step; function outer() { return () => { step++; return step; }; } step = 0; outer()() === 1"),
+        "true",
+        "chained capture of a top-level let update works in a nested arrow"
+    );
+}
+
+#[test]
+fn captured_top_let_simple_assign_in_stringify_setter() {
+    assert_eq!(
+        eval(
+            "let step; function setter() { step = 5; } function reader() { return step; } step = 0; JSON.stringify({}, (k, v) => { setter(); return reader(); }); step === 5"
+        ),
+        "true",
+        "captured top-level let simple assignment works from a stringify setter"
+    );
+}
+
+#[test]
+fn captured_top_let_update_in_named_replacer() {
+    assert_eq!(
+        eval(
+            "let step; function replacer(x, k, v) { step++; return x; } step = 0; JSON.stringify({}, (k, v) => replacer(2, k, v)); step === 1"
+        ),
+        "true",
+        "captured top-level let update works through an indirect named replacer"
+    );
+}
+
+#[test]
+fn captured_top_let_with_init_bare_read() {
+    assert_eq!(
+        eval("let step = 3; function r() { return step; } r() === 3"),
+        "true",
+        "captured top-level let with initializer reads through the closure"
+    );
+}
+
+#[test]
+fn function_decl_before_let_bare_read() {
+    // 函数声明在 let 之前（源序前），裸读经运行时 cell，声明后正常。
+    assert_eq!(
+        eval("function r() { return step; } let step; step = 0; r() === 0"),
+        "true",
+        "function declared before a captured let reads it after initialization"
+    );
+}
+
+// ── 箭头在 let 前：入口 TDZ 占位 cell 面（无编译期命中，运行时判定）──
+
+#[test]
+fn arrow_after_let_update_returns_new_value() {
+    assert_eq!(
+        eval("let step; const r = () => { step++; return step; }; step = 0; r() === 1"),
+        "true",
+        "arrow created after a captured let updates the binding"
+    );
+}
+
+#[test]
+fn arrow_before_let_update_returns_new_value() {
+    // 箭头先于 let 创建：入口 TDZ 占位 cell 使声明前读抛真 TDZ，
+    // 声明后 MAKE_CELL 原位翻转，更新正常。
+    assert_eq!(
+        eval("const r = () => { step++; return step; }; let step; step = 0; r() === 1"),
+        "true",
+        "arrow created before the captured let updates the binding after initialization"
+    );
+}
+
+// ── 捕获 const：写点 TypeError（TDZ 守卫跳过面不得吞 const 判定）──
+
+#[test]
+fn captured_top_const_update_throws_type_error() {
+    assert_eq!(
+        eval("const step = 1; function r() { step++; } try { r(); false } catch (e) { e.constructor === TypeError }"),
+        "true",
+        "updating a captured const throws TypeError, not a TDZ reference error"
+    );
+}
+
+#[test]
+fn captured_top_const_simple_assign_throws_type_error() {
+    assert_eq!(
+        eval("const step = 1; function r() { step = 2; return step; } try { r(); false } catch (e) { e.constructor === TypeError }"),
+        "true",
+        "assigning a captured const throws TypeError"
+    );
+}
+
+// ── 真 TDZ 保抛：声明语句执行前的读写仍抛 ReferenceError ──
+
+#[test]
+fn true_tdz_captured_let_update_throws_reference_error() {
+    // 声明语句在 try 块之后才执行：调用点命中入口 TDZ 占位 cell。
+    assert_eq!(
+        eval("function f() { x++; } try { f(); false } catch (e) { e.constructor === ReferenceError } let x = 1"),
+        "true",
+        "updating a captured let before its declaration throws ReferenceError"
+    );
+}
+
+#[test]
+fn true_tdz_captured_let_update_in_nested_depth() {
+    assert_eq!(
+        eval(
+            "function f() { x++; } JSON.stringify({}, (k, v) => { try { f(); } catch (e) { return e.constructor.name; } return v; }); let x = 1; x === 1"
+        ),
+        "true",
+        "true TDZ on a captured let survives builtin callback depth and stays catchable"
+    );
+}
+
+#[test]
+fn true_tdz_captured_let_bare_read_throws_inside_catcher() {
+    // 裸读真 TDZ 在捕获器内抛（结果未检视，仅锁"抛且可捕获"行为）。
+    assert_eq!(
+        eval(
+            "function r() { return step; } JSON.stringify({}, (k, v) => { try { String(r()); return 'no-throw'; } catch (e) { return e.constructor.name; } }); let step = 1; 'done' === 'done'"
+        ),
+        "true",
+        "bare read of a captured let before its declaration throws inside the catcher"
+    );
+}
+
+#[test]
+fn block_level_let_tdz_update_still_throws() {
+    // 块级 let 无嵌套捕获（纯静态 TDZ 面）：守卫跳过面不得波及，仍编译期抛。
+    assert_eq!(
+        eval("function f() { y = y + 1; let y; return y; } try { f(); false } catch (e) { e.constructor === ReferenceError }"),
+        "true",
+        "block-level let TDZ on an uncaptured binding still throws ReferenceError"
+    );
+}
+
+#[test]
+fn block_level_let_captured_closure_reads_updated_value() {
+    // 块级 let 被块内闭包捕获：块内声明后更新，块外读回更新值（重执行族对照面）。
+    assert_eq!(
+        eval("function g() { { let a = 5; const c = () => a; a = 6; return c; } return null; } g()() === 6"),
+        "true",
+        "closure over a block-level let reads the updated value after the block"
+    );
+}
+
+// ── 非捕获对照面：顶层 var / delete / typeof 不变 ──
+
+#[test]
+fn captured_top_var_update_after_decl() {
+    // 顶层 var 被捕获：入口即初始化为 undefined（提升语义），更新正常。
+    assert_eq!(
+        eval("var x; function r() { x++; return x; } x = 0; r() === 1 && x === 1"),
+        "true",
+        "captured top-level var update works, var hoisting semantics preserved"
+    );
+}
+
+#[test]
+fn delete_captured_top_let_returns_false() {
+    assert_eq!(
+        eval("let step = 1; function r() { return delete step; } r() === false && step === 1"),
+        "true",
+        "deleting a captured top-level let returns false and leaves the value"
+    );
+}
+
+#[test]
+fn typeof_captured_top_let_after_decl() {
+    assert_eq!(
+        eval("let step; function r() { return typeof step === 'number'; } step = 0; r()"),
+        "true",
+        "typeof on a captured top-level let after initialization reports number"
+    );
+}