An engine (drive force) control apparatus for a motorcycle that prevents a change in vehicle behavior by noise or the like. A control CPU electronically controls injection and ignition of fuel and a throttle valve. An abnormality detecting portion detects an abnormality of the engine control apparatus by a predetermined abnormality detecting period. When the abnormality is detected, primary abnormality processing of the engine control apparatus is executed. When the abnormality is not detected, primary abnormality processing is released and an electronic control at normal time of the engine control apparatus is executed. When an abnormality detecting signal detected by the abnormality detecting portion continues even an elapse of a predetermined abnormality determining time period, primary abnormality processing is shifted to secondary abnormality processing.