Engine operation control device for hybrid vehicle

An engine operation control device for a hybrid vehicle, including: an engine (2) provided in a vehicle (1); a power generator (9) that is driven by the engine (2) to generate electric power; a driving battery (11) that is chargeable with electric power supplied from the power generator (9); and a front motor (4) and a rear motor (6) that drive drive wheels with electric power supplied from the driving battery (11) or the power generator (9), and allowing a series mode in which the front motor (4) drives front wheels (3) and the rear motor (6) drives rear wheels (5) while the engine (2) is operated at a predetermined set rotational speed to drive the power generator (9) to generate electric power, wherein the set rotational speed is set to increase with decreasing of atmospheric pressure in a present position of the vehicle in the series mode.