The invention provides a control device of a hybrid vehicle. When a rotational fluctuation of the output rotational members of the transmission portion (for example, ring gears R of the planetary gearmechanism) is detected while the hybrid vehicle is travelling in the EV2 mode, the MG1 torque Tg becomes zero. Therefore, the increased amount of torque Tg resulting in a rotational fluctuation of the carrier CA of the planetary gear mechanism caused by the MG1 torque Tg is cancelled, and a shock input to the one-way clutch OWC is reduced. Thus, it is possible to restrain the deterioration of durability of the lock mechanism (one-way clutch OWC) against a rotational fluctuation of the third rotational element (ring gears R). In addition, in restraining the deterioration of durability of the one-way clutch OWC, reaction force caused by the MG1 torque Tg is not input to the ring gears R of the planetary gear mechanism, and thus, it is possible to restrain a shock or unintended deteriorationof the driving force.