diff --git a/src/entrypoints/set-has.d.ts b/src/entrypoints/set-has.d.ts
index 2da70da..af7b326 100644
--- a/src/entrypoints/set-has.d.ts
+++ b/src/entrypoints/set-has.d.ts
@@ -3,3 +3,7 @@
 interface Set<T> {
   has(value: T | (TSReset.WidenLiteral<T> & {})): boolean;
 }
+
+interface ReadonlySet<T> {
+  has(value: T | (TSReset.WidenLiteral<T> & {})): boolean;
+}
diff --git a/src/tests/set-has.ts b/src/tests/set-has.ts
index 288bf98..00a8042 100644
--- a/src/tests/set-has.ts
+++ b/src/tests/set-has.ts
@@ -15,3 +15,19 @@ doNotExecute(() => {
     true,
   );
 });
+
+doNotExecute(() => {
+  const set = new Set([1, 2, 3] as const) as ReadonlySet<1 | 2 | 3>;
+
+  set.has(4);
+
+  set.has(
+    // @ts-expect-error
+    "4",
+  );
+
+  set.has(
+    // @ts-expect-error
+    true,
+  );
+});