A controller for a vehicle includes an in-passenger-compartment temperature sensor which detects the temperature of the air supplied to an evaporator by actuating a blower fan, an outside air temperature sensor, an evaporator temperature sensor which detects the temperature of the evaporator, and an engine stop duration determiner which determines an engine stop duration on the basis of the temperature detected by the evaporator temperature sensor immediately before an engine stops and the temperatures detected by the outside air temperature sensor and the in-passenger-compartment temperature sensor. An engine control unit continues the operation of the blower fan after a stop condition holds and the engine is stopped, and then restarts the engine and actuates a compressor when the engine stop duration has elapsed.