diff --git a/tests/e2e/greptimedbcluster_baremetal_test.go b/tests/e2e/greptimedbcluster_baremetal_test.go
index 3cfe65a..e2919e6 100644
--- a/tests/e2e/greptimedbcluster_baremetal_test.go
+++ b/tests/e2e/greptimedbcluster_baremetal_test.go
@@ -121,6 +121,9 @@ var _ = Describe("Basic test of greptimedb cluster in baremetal", Ordered, func(
 		}
 		Expect(len(data) == testRowIDNum).Should(BeTrue(), "get the wrong data from db")
 
+		err = conn.Close()
+		Expect(err).NotTo(HaveOccurred(), "failed to close SQL connection")
+
 		err = createcmd.Process.Kill()
 		Expect(err).NotTo(HaveOccurred(), "failed to kill create cluster process")
 
diff --git a/tests/e2e/greptimedbcluster_test.go b/tests/e2e/greptimedbcluster_test.go
index 3d6e3c8..76b799c 100644
--- a/tests/e2e/greptimedbcluster_test.go
+++ b/tests/e2e/greptimedbcluster_test.go
@@ -102,7 +102,6 @@ var _ = Describe("Basic test of greptimedb cluster", Ordered, func() {
 			if err != nil {
 				return err
 			}
-
 			return nil
 		}, 30*time.Second, time.Second).ShouldNot(HaveOccurred())
 
@@ -136,6 +135,9 @@ var _ = Describe("Basic test of greptimedb cluster", Ordered, func() {
 		}
 		Expect(len(data) == testRowIDNum).Should(BeTrue(), "get the wrong data from db")
 
+		err = conn.Close()
+		Expect(err).NotTo(HaveOccurred(), "failed to close SQL connection")
+
 		err = deleteCluster()
 		Expect(err).NotTo(HaveOccurred(), "failed to delete cluster")
 	})