In a vane-type variable valve timing adjusting mechanism (VCT), an OCV target current is set to the holding current to hold an actual advance amount in close proximity to the target advance amount during the execution of the holding control. In the holding control, when the deviation between the actual and target advance amounts reaches beyond the holding control region (determination threshold value) and enters into the micro displacement control region, the micro displacement control (pulse-current application control) is started, and the pulse current is applied to the hydraulic control valve to use advantages of pulse current to drive the VCT in the direction of the target advance amount. Thus, when the actual advance amount comes back into close proximity to the target advance amount, the holding control is restarted, and the OCV target current is set to the holding current to hold the actual advance amount at the target advance amount.