An engine controller of the present invention is comprised of: a determining section for determining a state where an engine is not driven; a braking torque obtaining section for obtaining a braking toque acting on the vehicle; a vehicle speed sensing section for sensing a vehicle speed; an atmospheric pressure obtaining section for obtaining an atmospheric pressure value when an engine is driven; a road gradient obtaining section for obtaining a road gradient on the basis of the braking torque and the vehicle speed when the determining section determines the state where the vehicle is not driven; an atmospheric pressure correcting section which calculates a vehicle vertical travel of a downhill on the basis of the road gradient and a travel distance derived from the vehicle speed when the vehicle has descended the downhill, and corrects the atmospheric pressure value on the basis of the vehicle vertical travel of the downhill.