A vehicle apparatus comprising: a variable compression engine comprising a cylinder and a piston that is configured to reciprocally move in the cylinder; a variable compression ratio apparatus configured to adjust a movable range of the piston; and at least one controller configured to cause the variable compression ratio apparatus to change a compression ratio when determined that a driving condition of a vehicle and a stability condition of the engine are satisfied to change a compression ratio and further configured to control a motor and the engine to adjust a motor torque and an engine torque to meet a torque requirement for operating the vehicle, wherein a driving condition of the vehicle is satisfied if an operating point of the engine exists in a predetermined range, a vehicle speed is a predetermined speed or more, and a speed stage is a predetermined speed stage or higher, and wherein a stability condition of the engine is satisfied if an atmospheric pressure is a predetermined pressure or more, a driving time of the vehicle after the engine starting is a predetermined time or more, a fuel temperature is a predetermined temperature or less, a coolant temperature is a predetermined temperature or more, the engine torque is within a predetermined range during a predetermined time, an engine speed is within a predetermined range during a predetermined time, an air amount inflowing to the cylinder is within a predetermined range during a predetermined time, a driving mode is not a generation mode of an exhaust gas processing device, and a predetermined time is exceeded after the compression ratio change is executed through the variable compression ratio apparatus. a variable compression engine comprising a cylinder and a piston that is configured to reciprocally move in the cylinder; a variable compression ratio apparatus configured to adjust a movable range of the piston; and at least one controller configured to cause the variable compression ratio apparatus to change a compression ratio when determined that a driving condition of a vehicle and a stability condition of the engine are satisfied to change a compression ratio and further configured to control a motor and the engine to adjust a motor torque and an engine torque to meet a torque requirement for operating the vehicle, wherein a driving condition of the vehicle is satisfied if an operating point of the engine exists in a predetermined range, a vehicle speed is a predetermined speed or more, and a speed stage is a predetermined speed stage or higher, and wherein a stability condition of the engine is satisfied if an atmospheric pressure is a predetermined pressure or more, a driving time of the vehicle after the engine starting is a predetermined time or more, a fuel temperature is a predetermined temperature or less, a coolant temperature is a predetermined temperature or more, the engine torque is within a predetermined range during a predetermined time, an engine speed is within a predetermined range during a predetermined time, an air amount inflowing to the cylinder is within a predetermined range during a predetermined time, a driving mode is not a generation mode of an exhaust gas processing device, and a predetermined time is exceeded after the compression ratio change is executed through the variable compression ratio apparatus.