In a driving condition control system, a sensing unit senses a first physical quantity indicative of a rotation of the first rotatable axle assembly and a second physical quantity indicative of a rotation of the second rotatable axle assembly. A determining unit compares the first and second physical quantities of the rotations of the first and second rotational axle assemblies and determines whether a driving condition of the vehicle is unstable according to the compared result. As a result, the unstable condition of the vehicle can be rapidly detected without detecting a yaw moment of the vehicle.