To eliminate nonconformities when stopping an engine, such as a driven member being not turned to a position by more than a predetermined intermediate position, in relation to a driven member by the lowering of an oil pressure resulting from the elevation of hydraulic oil temperature.

When the oil pressure lowers at an idling operation due to high oil temperature, it is elevated by increasing an idling revolution, thereby, a vane rotor 7 can surely be driven to an advance angle side at engine stop. Furthermore, since the vane rotor 7 is positioned at the side which is advanced from a most delayed angle position, it is possible to lessen the advance angle amount for advancing the vane rotor 7 to a predetermined intermediate phase, when stopping the engine, thus enabling further ensured drive of the vane rotor 7 to the advancing angle side at engine stoppage.