When a pump operates, a check valve body leaves a check valve seat due to a pump side fuel pressure for opening a fluid passage inside a pressure adjusting valve body. When the pump does not operate, the check valve body contacts the check valve seat due to an engine side fuel pressure for closing the fluid passage. Thus, the engine side fuel is prevented from flowing-back to the pump. When the pump stops operating and the engine side fuel pressure exceeds a pressure corresponding to an urging force of a coil spring, the pressure adjusting valve body leaves the pressure adjusting valve seat with the check valve body, so that a gap is provided between the pressure adjusting valve body and the pressure adjusting valve seat for releasing the engine side fuel having excess pressure.