This control device is applied to a hybrid vehicle that is provided with a motor lock mechanism that changes over the state of a power distribution mechanism between a differentiating state in which a differentially rotating state between an engine and a first motor-generator is permitted, and a non-differentiating state in which the rotation of the first motor-generator is prohibited. The control device stops combustion by the engine and changes over to an EV mode when predetermined conditions become valid during implementation by the power distribution mechanism of a differentiating mode of the differentiating state or of a non-differentiating mode of the non-differentiating state. The condition is set to be more severe while the non-differentiating mode is being implemented, as compared with the case while the differentiating mode is being implemented.