diff --git a/.changeset/nice-oranges-mate.md b/.changeset/nice-oranges-mate.md
new file mode 100644
index 00000000..09821507
--- /dev/null
+++ b/.changeset/nice-oranges-mate.md
@@ -0,0 +1,5 @@
+---
+"@solidjs/router": patch
+---
+
+Support `in` operator for useParams()
diff --git a/src/utils.ts b/src/utils.ts
index eb0c0b1c..d347fb2f 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -158,6 +158,9 @@ export function createMemoObject<T extends Record<string | symbol, unknown>>(fn:
     },
     ownKeys() {
       return Reflect.ownKeys(fn());
+    },
+    has(_, property) {
+      return property in fn();
     }
   });
 }