A valve timing control system includes: a check valve which is provided between an oil pump driven by the engine, and the lock release passage; an electromagnetic valve which is disposed between the check valve and the lock release passage; an accumulator disposed between the check valve and the electromagnetic valve; and a passage which is disposed between the check valve and the electromagnetic valve, in which the flow of the oil is stored, and which is arranged to release the restriction of the lock mechanism by a pressure of the accumulator by energizing the valve driving solenoid of the electromagnetic valve.