Slip control is carried out so as to reduce torque applied to the driven wheels by reducing torque generated by the engine when a slip value against the driven wheels on pavement is larger than a predetermined value. A shift characteristic of the automatic transmission interposed between the engine and the driven wheels is set as a first shift characteristic which is a basic characteristic at the time of ordinary running where no slip control is carried out and as a second shift characteristic set so as to become at least unlikely to cause downshifting during slip control compared with said first shift characteristic. As the slip control terminates, a return of the first shift characteristic is prohibited when the torque generated by the engine is large (for example, when a degree of operation of an accelerator is not zero) or when downshifting is caused if based on the first shift characteristics.