diff --git a/crates/oxide_builtins/src/json.rs b/crates/oxide_builtins/src/json.rs
index bd9a2b47..3e11e390 100644
--- a/crates/oxide_builtins/src/json.rs
+++ b/crates/oxide_builtins/src/json.rs
@@ -195,13 +195,20 @@ fn key_si_to_units<H: VmHost>(vm: &H, si: u32) -> Vec<u16> {
 }
 
 fn call_to_json<H: VmHost>(vm: &mut H, obj_val: JsValue, key: &[u16]) -> Result<JsValue, JsValue> {
-    if !obj_val.is_object() {
-        return Ok(obj_val);
-    }
-    let obj_ptr = obj_val.as_js_object_ptr();
-    if obj_ptr.is_null() {
+    // SerializeJSONProperty 步 2：对象与 BigInt 原语均查 toJSON（Get 对原语
+    // 自动装箱），BigInt 的查表对象取 %BigIntPrototype%。
+    if !obj_val.is_object() && !obj_val.is_bigint() {
         return Ok(obj_val);
     }
+    let obj_ptr = if obj_val.is_object() {
+        let p = obj_val.as_js_object_ptr();
+        if p.is_null() {
+            return Ok(obj_val);
+        }
+        p
+    } else {
+        vm.session().builtin_world().bigint_proto.as_ptr() as *mut JsObject
+    };
     let tojson_si = vm.kernel_core().perm_interner().intern("toJSON").0;
     let resolved = vm.resolve_property(unsafe { &*obj_ptr }, tojson_si);
     match resolved {
@@ -349,6 +356,9 @@ fn jsvalue_to_json<H: VmHost>(
         } else {
             oxide_runtime_api::write_number_into(n, out);
         }
+    } else if val.is_bigint() {
+        // SerializeJSONProperty 步 10：BigInt 无 JSON 文本形态，抛 TypeError。
+        return Err(crate::error::create_type_error(vm, "Do not know how to serialize a BigInt"));
     } else if val.is_string() {
         // SAFETY: val 已确认是字符串值；单元视图按码单元流序列化（见 stringify_string_units）。
         let units = unsafe { (*val.as_string_ptr()).units() };
@@ -365,7 +375,13 @@ fn jsvalue_to_json<H: VmHost>(
         }
 
         let obj = unsafe { &*obj_ptr };
-        if obj.is_array() {
+        // 步 4d：装箱 BigInt 无条件解包 [[BigIntData]]，后续步 10 抛 TypeError。
+        if obj.boxed_value().is_bigint() {
+            return Err(crate::error::create_type_error(vm, "Do not know how to serialize a BigInt"));
+        }
+        if obj.is_typed_array_obj() {
+            stringify_typed_array(vm, obj, visited, out, replacer_fn, replacer_whitelist, space, indent_level)?;
+        } else if obj.is_array() {
             stringify_array(vm, obj, visited, out, replacer_fn, replacer_whitelist, space, indent_level)?;
         } else {
             stringify_object(vm, obj, visited, out, replacer_fn, replacer_whitelist, space, indent_level)?;
@@ -584,3 +600,89 @@ fn stringify_array<H: VmHost>(
     out.push(']');
     Ok(())
 }
+
+/// TypedArray 序列化：整数索引是可枚举自身属性（元素存于原生载荷，不在形状链），
+/// 逐元素按对象臂规范序 Get → toJSON → replacer 处理，输出形态与普通对象一致。
+#[allow(clippy::too_many_arguments)]
+fn stringify_typed_array<H: VmHost>(
+    vm: &mut H, obj: &JsObject, visited: &mut HashSet<*const JsObject>, out: &mut String, replacer_fn: Option<JsValue>,
+    replacer_whitelist: Option<&HashSet<String>>, space: &str, indent_level: usize,
+) -> Result<(), JsValue> {
+    let has_space = !space.is_empty();
+    let this_val = JsValue::from_js_object(obj as *const JsObject as *mut JsObject);
+    let view = crate::typed_array::get_typed_array_data(vm, this_val)?;
+    out.push('{');
+    let mut first = true;
+    for i in 0..view.length {
+        let index_str = i.to_string();
+        // 白名单判定先于 Get（SerializeJSONObject 步 4a），非白名单键不读元素。
+        if let Some(whitelist) = replacer_whitelist {
+            if !whitelist.contains(&index_str) {
+                continue;
+            }
+        }
+        let index_units: Vec<u16> = index_str.encode_utf16().collect();
+        let val = crate::typed_array::typed_array_element_get(vm, obj, i as u32)
+            .map_err(|msg| crate::error::create_type_error(vm, &msg))?;
+        let val = call_to_json(vm, val, &index_units)?;
+
+        // replacer 函数回调。
+        let val = if let Some(replacer) = replacer_fn {
+            let key_val = vm.new_string(&index_str);
+            match vm.call_function_sync(replacer, this_val, &[key_val, val]) {
+                Ok(v) => {
+                    if v.is_undefined() {
+                        continue;
+                    }
+                    v
+                }
+                Err(msg) => {
+                    let exc = vm
+                        .take_uncaught_value()
+                        .unwrap_or_else(|| crate::error::create_type_error(vm, &msg));
+                    return Err(exc);
+                }
+            }
+        } else {
+            val
+        };
+
+        let is_function = val.is_object() && {
+            let ptr = val.as_js_object_ptr();
+            !ptr.is_null() && unsafe { (*ptr).is_function() }
+        };
+        if val.is_undefined() || is_function {
+            continue;
+        }
+
+        if !first && !has_space {
+            out.push(',');
+        } else if !first {
+            out.push_str(",\n");
+        }
+        first = false;
+
+        if has_space {
+            for _ in 0..indent_level + 1 {
+                out.push_str(space);
+            }
+            stringify_string_units(&index_units, out);
+            out.push(':');
+            out.push(' ');
+        } else {
+            stringify_string_units(&index_units, out);
+            out.push(':');
+        }
+
+        jsvalue_to_json(vm, val, visited, out, replacer_fn, replacer_whitelist, space, indent_level + 1)?;
+    }
+
+    if has_space && !first {
+        out.push('\n');
+        for _ in 0..indent_level {
+            out.push_str(space);
+        }
+    }
+    out.push('}');
+    Ok(())
+}
diff --git a/crates/oxide_builtins/tests/builtins_json_tests.rs b/crates/oxide_builtins/tests/builtins_json_tests.rs
index f88d5c53..6638893f 100644
--- a/crates/oxide_builtins/tests/builtins_json_tests.rs
+++ b/crates/oxide_builtins/tests/builtins_json_tests.rs
@@ -322,6 +322,113 @@ fn stringify_array_ignores_named_props() {
     assert_eq!(out, "[1,2]");
 }
 
+// --- BigInt 值位（SerializeJSONProperty 步 10 抛 TypeError；步 2 查 toJSON）---
+
+fn assert_bigint_serialize_err(source: &str) {
+    let result = eval(source);
+    match result {
+        Err(e) => {
+            assert!(
+                e.to_lowercase().contains("do not know how to serialize a bigint"),
+                "expected BigInt serialize TypeError, got: {}",
+                e
+            )
+        }
+        Ok(_) => panic!("expected BigInt serialize TypeError, got ok: {}", source),
+    }
+}
+
+// 顶层原语四值位：1n / -1n / 0n / -0n 恒抛，无文本产出。
+#[test]
+fn stringify_bigint_top_level_throws() {
+    assert_bigint_serialize_err("JSON.stringify(1n)");
+    assert_bigint_serialize_err("JSON.stringify(-1n)");
+    assert_bigint_serialize_err("JSON.stringify(0n)");
+    assert_bigint_serialize_err("JSON.stringify(-0n)");
+}
+
+// 大位宽 BigInt 同样抛错（不产十进制文本）。
+#[test]
+fn stringify_bigint_wide_bits_throws() {
+    assert_bigint_serialize_err("JSON.stringify(2n ** 32n + 1n)");
+}
+
+// 嵌套对象属性与数组元素位（含深嵌套、稀疏）均经值位臂抛错。
+#[test]
+fn stringify_bigint_nested_throws() {
+    assert_bigint_serialize_err("JSON.stringify({a:1n})");
+    assert_bigint_serialize_err("JSON.stringify([1n,2n,[3n]])");
+    assert_bigint_serialize_err("JSON.stringify({a:{b:1n}})");
+    assert_bigint_serialize_err("JSON.stringify([,1n])");
+}
+
+// 空格缩进不改变抛错路径。
+#[test]
+fn stringify_bigint_space_indent_throws() {
+    assert_bigint_serialize_err("JSON.stringify({a:1n}, null, 2)");
+}
+
+// replacer 白名单命中键后仍走值位抛错。
+#[test]
+fn stringify_bigint_whitelist_throws() {
+    assert_bigint_serialize_err("JSON.stringify({a:1n}, ['a'])");
+}
+
+// 装箱 BigInt（步 4d 无条件解包 [[BigIntData]]）与裸值同抛。
+#[test]
+fn stringify_bigint_boxed_throws() {
+    assert_bigint_serialize_err("JSON.stringify(Object(0n))");
+    assert_bigint_serialize_err("JSON.stringify({a:Object(1n)})");
+}
+
+// BigInt64Array 元素位经对象臂读值后在值位臂抛错。
+#[test]
+fn stringify_bigint64array_throws() {
+    assert_bigint_serialize_err("JSON.stringify(new BigInt64Array([1n,2n]))");
+}
+
+// replacer 透传不改变值位；replacer 结果再入值位臂同样抛错。
+#[test]
+fn stringify_bigint_replacer_throws() {
+    assert_bigint_serialize_err("JSON.stringify(1n, (k,v) => v)");
+    assert_bigint_serialize_err("JSON.stringify({a:1n}, (k,v) => v)");
+    assert_bigint_serialize_err("JSON.stringify({a:1}, (k,v) => 2n)");
+}
+
+// BigInt.prototype 挂数据属性 toJSON：钩子被触发，返回串值正常序列化。
+#[test]
+fn stringify_bigint_tojson_hook_top_level() {
+    let out = eval_str(
+        "(() => { BigInt.prototype.toJSON = function(){ return this.toString(); }; \
+         const s = JSON.stringify(0n); \
+         delete BigInt.prototype.toJSON; \
+         return s; })()",
+    )
+    .unwrap();
+    assert_eq!(out, r#""0""#);
+}
+
+// toJSON 钩子嵌套对象属性位：receiver 为 BigInt 原语，this.toString() 生效。
+#[test]
+fn stringify_bigint_tojson_hook_nested() {
+    let out = eval_str(
+        "(() => { BigInt.prototype.toJSON = function(){ return this.toString(); }; \
+         const s = JSON.stringify({a:1n}); \
+         delete BigInt.prototype.toJSON; \
+         return s; })()",
+    )
+    .unwrap();
+    assert_eq!(out, r#"{"a":"1"}"#);
+}
+
+// 守卫：replacer 先于值位转换 BigInt → number，不抛错。
+#[test]
+fn stringify_bigint_replacer_transform_guard() {
+    let out = eval_str("JSON.stringify({b:1n}, function(k,v){ if(typeof v==='bigint') return Number(v); return v; })")
+        .unwrap();
+    assert_eq!(out, r#"{"b":1}"#);
+}
+
 fn eval_str(source: &str) -> Result<String, String> {
     let (vm, result) = eval(source)?;
     vm.lookup_str(result)