diff --git a/common/mock_prefs.h b/common/mock_prefs.h
new file mode 100644
index 0000000..0e639a2
--- /dev/null
+++ b/common/mock_prefs.h
@@ -0,0 +1,51 @@
+//
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_COMMON_MOCK_PREFS_H_
+#define UPDATE_ENGINE_COMMON_MOCK_PREFS_H_
+
+#include <string>
+
+#include <gmock/gmock.h>
+
+#include "update_engine/common/constants.h"
+#include "update_engine/common/prefs_interface.h"
+
+namespace chromeos_update_engine {
+
+class MockPrefs : public PrefsInterface {
+ public:
+  MOCK_CONST_METHOD2(GetString,
+                     bool(const std::string& key, std::string* value));
+  MOCK_METHOD2(SetString, bool(const std::string& key,
+                               const std::string& value));
+  MOCK_CONST_METHOD2(GetInt64, bool(const std::string& key, int64_t* value));
+  MOCK_METHOD2(SetInt64, bool(const std::string& key, const int64_t value));
+
+  MOCK_CONST_METHOD2(GetBoolean, bool(const std::string& key, bool* value));
+  MOCK_METHOD2(SetBoolean, bool(const std::string& key, const bool value));
+
+  MOCK_CONST_METHOD1(Exists, bool(const std::string& key));
+  MOCK_METHOD1(Delete, bool(const std::string& key));
+
+  MOCK_METHOD2(AddObserver, void(const std::string& key, ObserverInterface*));
+  MOCK_METHOD2(RemoveObserver,
+               void(const std::string& key, ObserverInterface*));
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_COMMON_MOCK_PREFS_H_