diff --git a/builtin/providers/aws/resource_aws_redshift_cluster_test.go b/builtin/providers/aws/resource_aws_redshift_cluster_test.go
index fb9a35caf..f44bb158e 100644
--- a/builtin/providers/aws/resource_aws_redshift_cluster_test.go
+++ b/builtin/providers/aws/resource_aws_redshift_cluster_test.go
@@ -566,6 +566,10 @@ func TestResourceAWSRedshiftClusterMasterPasswordValidation(t *testing.T) {
 			Value:    "1Testing",
 			ErrCount: 0,
 		},
+		{
+			Value:    "1Testing@",
+			ErrCount: 1,
+		},
 	}
 
 	for _, tc := range cases {