To properly operate an engine brake according to a vehicle running condition in each case, and to stabilize vehicle behavior in operation.

An engine 10 is provided with an intake valve 15 and an exhaust valve 16 opened in respective intake and exhaust processes, and the respective valves 15, 16 are provided with valve drive mechanisms 20, 21 which arbitrarily controls opening/closing states. An ECU 30 decides necessity of generation of deceleration torque according to a vehicle running condition in each time. When it is decided that the deceleration torque is necessary, the ECU 30 controls the valve drive mechanisms 20, 21 to reduce a valve opening degree of at least one of the intake valve 15 and the exhaust valve 16 until a target deceleration state is accomplished.