To properly restrain efficiency lowering of a hybrid vehicle.

Power circulation is avoided by stopping rotation of a motor generator with engagement of a brake to be fixed (S103, S104), when a rotation speed Ng of the motor generator is negative (direction reverse to a rotational direction of an engine). A required rotation speed Ng0 of the motor generator is calculated under a high efficiency condition where a speed Ne of an engine 50 is consistent with the required rotation speed Ng0 on an optimum fuel consumption line (S106), when the brake is engaged, and the brake is released to release the rotation speed of the motor generator (S107, S108), when the required rotation speed Ng0 is a positive prescribed value Ng1 or more (direction same to the direction of the rotational direction of the engine).

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