Abstract: A control device for a transmission that has multiple shift stages and is configured to change an amount of power output from an engine of a vehicle for output includes a setting unit and a control unit. The setting unit is capable of setting, as a shift change mode, either one of a first shift change mode and a second shift change mode in which a speed of the engine is maintained in a higher state than that in the first shift change mode. The control unit is configured to execute shift change control on a basis of the set shift change mode. The control unit is configured to exclude one or more shift stages of the multiple shift stages and execute the shift change control when the second shift change mode is set.