Providing a control apparatus for a variable-cylinder engine or a vehicle control apparatus, which permits a further improvement in the fuel economy of the vehicleDecompression-state setting means 102 is arranged to place appropriate ones of non-operating cylinders of the variable-cylinder engine 10 in the decompression state, on the basis of regenerative braking state of vehicle detected by regenerative-braking-state detecting means 100, so that only a required minimum number of the non-operating cylinders of the variable-cylinder engine 10 is/are placed in the decompression state, depending upon the detected regenerative braking state of the vehicle, making it possible to not only improve fuel economy of the vehicle but also assure sufficient engine braking of the vehicle.