diff --git a/tests/integration/helpers.ts b/tests/integration/helpers.ts
index 903ceb70..e25ee222 100644
--- a/tests/integration/helpers.ts
+++ b/tests/integration/helpers.ts
@@ -83,6 +83,9 @@ export function setupIntegrationTest(): IntegrationTest {
     afterEach(async () => {
         await mcpServer?.session.close();
         config.connectionString = undefined;
+
+        await mongoClient?.close();
+        mongoClient = undefined;
     });
 
     beforeAll(async function () {