diff --git a/amoro-ams/src/test/java/org/apache/amoro/server/RestCatalogServiceTestBase.java b/amoro-ams/src/test/java/org/apache/amoro/server/RestCatalogServiceTestBase.java
index 5a3c4aa82d..9bf32f904f 100644
--- a/amoro-ams/src/test/java/org/apache/amoro/server/RestCatalogServiceTestBase.java
+++ b/amoro-ams/src/test/java/org/apache/amoro/server/RestCatalogServiceTestBase.java
@@ -43,13 +43,16 @@
 
 import java.io.IOException;
 import java.util.Map;
+import java.util.concurrent.atomic.AtomicLong;
 
 public abstract class RestCatalogServiceTestBase {
 
   static AmsEnvironment ams = AmsEnvironment.getIntegrationInstances();
   static String restCatalogUri = RestCatalogService.ICEBERG_REST_API_PREFIX;
 
-  protected final String database = "test_ns";
+  private static final AtomicLong TEST_INSTANCE_COUNTER = new AtomicLong();
+
+  protected final String database = "test_ns_" + TEST_INSTANCE_COUNTER.incrementAndGet();
   protected final String table = "test_iceberg_tbl";
   protected final TableIdentifier tableIdentifier =
       TableIdentifier.of(catalogName(), database, table);
diff --git a/amoro-ams/src/test/java/org/apache/amoro/server/TestInternalIcebergCatalogService.java b/amoro-ams/src/test/java/org/apache/amoro/server/TestInternalIcebergCatalogService.java
index 19d4ace8a7..3a5ea9e1c0 100644
--- a/amoro-ams/src/test/java/org/apache/amoro/server/TestInternalIcebergCatalogService.java
+++ b/amoro-ams/src/test/java/org/apache/amoro/server/TestInternalIcebergCatalogService.java
@@ -104,12 +104,18 @@ public void testCatalogProperties() {
   public class NamespaceTests {
     @Test
     public void testNamespaceOperations() throws IOException {
-      Assertions.assertTrue(nsCatalog.listNamespaces().isEmpty());
-      nsCatalog.createNamespace(Namespace.of(database));
-      Assertions.assertEquals(1, nsCatalog.listNamespaces().size());
-      Assertions.assertEquals(0, nsCatalog.listNamespaces(Namespace.of(database)).size());
-      nsCatalog.dropNamespace(Namespace.of(database));
-      Assertions.assertTrue(nsCatalog.listNamespaces().isEmpty());
+      Namespace dbNamespace = Namespace.of(database);
+      int initialNamespaceCount = nsCatalog.listNamespaces().size();
+      Assertions.assertFalse(nsCatalog.listNamespaces().contains(dbNamespace));
+
+      nsCatalog.createNamespace(dbNamespace);
+      Assertions.assertEquals(initialNamespaceCount + 1, nsCatalog.listNamespaces().size());
+      Assertions.assertTrue(nsCatalog.listNamespaces().contains(dbNamespace));
+      Assertions.assertEquals(0, nsCatalog.listNamespaces(dbNamespace).size());
+
+      nsCatalog.dropNamespace(dbNamespace);
+      Assertions.assertEquals(initialNamespaceCount, nsCatalog.listNamespaces().size());
+      Assertions.assertFalse(nsCatalog.listNamespaces().contains(dbNamespace));
     }
   }
 
diff --git a/amoro-ams/src/test/java/org/apache/amoro/server/TestInternalMixedCatalogService.java b/amoro-ams/src/test/java/org/apache/amoro/server/TestInternalMixedCatalogService.java
index 3e24e42b61..65e8d387bd 100644
--- a/amoro-ams/src/test/java/org/apache/amoro/server/TestInternalMixedCatalogService.java
+++ b/amoro-ams/src/test/java/org/apache/amoro/server/TestInternalMixedCatalogService.java
@@ -165,16 +165,20 @@ public void test() {
       MixedFormatCatalog catalog = loadMixedIcebergCatalog();
       Assertions.assertEquals(
           InternalMixedIcebergCatalog.class.getName(), catalog.getClass().getName());
-      Assertions.assertTrue(catalog.listDatabases().isEmpty());
+      int initialDatabaseCount = catalog.listDatabases().size();
+      int initialNamespaceCount = nsCatalog.listNamespaces(Namespace.of()).size();
+      Assertions.assertFalse(catalog.listDatabases().contains(database));
 
       catalog.createDatabase(database);
-      Assertions.assertEquals(1, catalog.listDatabases().size());
+      Assertions.assertEquals(initialDatabaseCount + 1, catalog.listDatabases().size());
       Assertions.assertTrue(catalog.listDatabases().contains(database));
-      Assertions.assertEquals(1, nsCatalog.listNamespaces(Namespace.of()).size());
+      Assertions.assertEquals(
+          initialNamespaceCount + 1, nsCatalog.listNamespaces(Namespace.of()).size());
 
       catalog.dropDatabase(database);
-      Assertions.assertTrue(catalog.listDatabases().isEmpty());
-      Assertions.assertTrue(nsCatalog.listNamespaces().isEmpty());
+      Assertions.assertEquals(initialDatabaseCount, catalog.listDatabases().size());
+      Assertions.assertFalse(catalog.listDatabases().contains(database));
+      Assertions.assertEquals(initialNamespaceCount, nsCatalog.listNamespaces().size());
     }
   }