An engine control or registration control apparatus, which is to be mounted on a vehicle is provided. The control device includes a gear state determination module for determining a connection between a step transmission and a motor, a determination that a gear change has started, if the compound is released from a connected state or disconnected and determining that the gear change has been completed when the connection is resumed, a gear position judging module for judging a gear position if it is determined to change gear that he has started, a target motor speed specification module for specifying a target motor speed based on the estimated gear position, and a speed regulation or control module for controlling an engine speed to the target engine speed when it is intended for the speed change, that it is started.