diff --git a/services/sandbox_manager/main/cpp/src/database/sandbox_manager_rdb.cpp b/services/sandbox_manager/main/cpp/src/database/sandbox_manager_rdb.cpp
index fafcd0dc91636b2a6b3a50a2eba2cea3a97538ff..738f4bdee169db1dd926a2063ad4b194331c6937 100644
--- a/services/sandbox_manager/main/cpp/src/database/sandbox_manager_rdb.cpp
+++ b/services/sandbox_manager/main/cpp/src/database/sandbox_manager_rdb.cpp
@@ -239,6 +239,10 @@ int32_t SandboxManagerRdb::FindSubPath(
     SANDBOXMANAGER_LOG_DEBUG(LABEL, "Find tableName: %{public}s", tableName.c_str());
 
     OHOS::Utils::UniqueReadGuard<OHOS::Utils::RWLock> lock(this->rwLock_);
+    if (db_ == nullptr) {
+        SANDBOXMANAGER_LOG_ERROR(LABEL, "Db is null, open db first");
+        return FAILURE;
+    }
     std::vector<NativeRdb::ValueObject> bindArgs;
     std::string like_arg_str = filePath + "/%";
     NativeRdb::ValueObject arg1(like_arg_str);