In a vehicle air conditioner, a compressor is driven by a vehicle engine when an actual temperature of an evaporator is higher than a basis temperature that is higher than a target temperature by a predetermined temperature, and is driven by an electrical motor when the actual temperature of the evaporator is lower than the basis temperature. The predetermined temperature is set to be higher as the target temperature of the evaporator decreases such that the basis temperature is not higher than a comfortable limit temperature. Accordingly, the compressor can be driven by the electrical motor in a range where the actual temperature can be controlled to be not higher than the comfortable limit temperature. Therefore, fuel consumption efficiency of the engine can be improved, while a minimum of cooling capacity can be ensured.