A vehicle control device having a tire air pressure detecting unit for detecting tire air pressure of a vehicle having an engine mounted in the vehicle and outputting a tire air pressure signal, a tire air pressure reduction judging unit for judging on the basis of the tire air pressure signal whether the tire air pressure is reduced to predetermined pressure or less, and an output varying unit for varying driving force of the engine to tires according to a predetermined varying function on the basis of the judgment result. Even if a driver does not perceive an alarm when reduction of tire air pressure is detected, a driving system such as an engine, a transmission and a clutch is controlled according to a predetermined varying function. Therefore, for example, the rotational speed of the engine is periodically varied, and thus the driver has an uncomfortable feeling. Therefore, the driver can surely recognize the reduction of the tire pressure.