diff --git a/src/Senparc.AI.Kernel/KernelConfigExtensions/KernelConfigExtensions.cs b/src/Senparc.AI.Kernel/KernelConfigExtensions/KernelConfigExtensions.cs
index 760ba86..082ea95 100644
--- a/src/Senparc.AI.Kernel/KernelConfigExtensions/KernelConfigExtensions.cs
+++ b/src/Senparc.AI.Kernel/KernelConfigExtensions/KernelConfigExtensions.cs
@@ -244,7 +244,6 @@ public static VectorStoreCollection<TKey, TRecord> GetVectorCollection<TKey, TRe
              where TRecord : class
         {
             IDatabase database;
-            VectorStore vectorStore;
             VectorStoreCollection<TKey, TRecord> collection = null;
 
             //TODO: If the logic becomes overly complex in the future, different combinations can be considered to be separated into different libraries
@@ -253,8 +252,10 @@ public static VectorStoreCollection<TKey, TRecord> GetVectorCollection<TKey, TRe
             {
                 case VectorDBType.Memory:
                     {
-                        vectorStore = new InMemoryVectorStore();
-                        collection = vectorStore.GetCollection<TKey, TRecord>(name, vectorStoreRecordDefinition);
+                        using (var inMemoryVectorStore = new InMemoryVectorStore())
+                        {
+                            collection = inMemoryVectorStore.GetCollection<TKey, TRecord>(name, vectorStoreRecordDefinition);
+                        }
                         break;
                     }
                 case VectorDBType.HardDisk:
@@ -293,13 +294,17 @@ public static VectorStoreCollection<TKey, TRecord> GetVectorCollection<TKey, TRe
                     }
                 case VectorDBType.Qdrant:
                     {
-                        vectorStore = new QdrantVectorStore(new QdrantClient(vectorDb.ConnectionString), ownsClient: true);
-                        collection = vectorStore.GetCollection<TKey, TRecord>(name, vectorStoreRecordDefinition);
+                        using (var qdrantVectorStore = new QdrantVectorStore(new QdrantClient(vectorDb.ConnectionString), ownsClient: true))
+                        {
+                            collection = qdrantVectorStore.GetCollection<TKey, TRecord>(name, vectorStoreRecordDefinition);
+                        }
                         break;
                     }
                 default:
-                    vectorStore = new InMemoryVectorStore();
-                    collection = vectorStore.GetCollection<TKey, TRecord>(name, vectorStoreRecordDefinition);
+                    using (var inMemoryVectorStore = new InMemoryVectorStore())
+                    {
+                        collection = inMemoryVectorStore.GetCollection<TKey, TRecord>(name, vectorStoreRecordDefinition);
+                    }
                     break;
             }