A control device of a hybrid vehicle includes: a map defined by an accelerator opening degree and a vehicle speed and in which an infinite variable speed mode and a fixed speed change mode are set; and a control means which switches the speed change mode in accordance with the movement of the vehicle operation point on the map. The fixed speed change mode area includes: a first fixed speed change mode area in which the reaction torque becomes equal to or smaller than the maximum rating torque of the motor generator, and a second fixed speed change mode area in which the reaction torque becomes larger than the maximum rating torque. The control means differentiates the speed change mode switching method in accordance with which one of the first and the second fixed speed change mode areas the vehicle operation point locates in or moves to.