Speed changing control system for a vehicle

Disclosed is a speed changing control system for a vehicle including a speed changing device 2 for speed changing a rotational power from an engine 1 and outputting the resultant speed-changed power, a speed changing control unit 6 for setting a speed change ratio of the speed changing device 2, and an engine control unit 5 for setting an engine rotational speed of the engine. According to the system, based on an operational instruction in response to a driver's operation, a rotational speed reducing instruction is given to the engine control unit 5 for reducing an engine rotational speed set by the engine control unit by a predetermined amount. Also, a speed changing ratio changing instruction is given to the engine control unit 5 for requesting, to a speed changing control unit 6, a change of the speed change ratio for compensating for the reduction in the engine rotational speed by the rotational speed reducing instruction so as to maintain the vehicle speed.