diff --git a/src/index.ts b/src/index.ts
index ea6977d..38e0f9a 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -106,7 +106,11 @@ const _parseJSON = (jsonString: string, allow: number) => {
                 index++; // skip colon
                 try {
                     const value = parseAny();
-                    obj[key] = value;
+                    if (key === "__proto__") {
+                        Object.defineProperty(obj, key, { value, writable: true, enumerable: true, configurable: true });
+                    } else {
+                        obj[key] = value;
+                    }
                 } catch (e) {
                     if (Allow.OBJ & allow) return obj;
                     else throw e;
diff --git a/src/proto.test.ts b/src/proto.test.ts
new file mode 100644
index 0000000..e33855c
--- /dev/null
+++ b/src/proto.test.ts
@@ -0,0 +1,16 @@
+import { describe, expect, it } from "vitest";
+import { parse } from "./index";
+
+describe("object key parsing", () => {
+    it("preserves __proto__ as an own enumerable key", () => {
+        const value = parse('{"__proto__":0}');
+        const descriptor = Object.getOwnPropertyDescriptor(value, "__proto__");
+
+        expect(descriptor).toMatchObject({
+            value: 0,
+            writable: true,
+            enumerable: true,
+            configurable: true,
+        });
+    });
+});