A vehicle motion control device includes curve shape acquisition means for acquiring a shape of a curve present in front of a currently traveling vehicle, vehicle position acquisition means for acquiring a position of the vehicle, and vehicle motion control arithmetic means for computing, on the basis of the shape of the curve and the position of the vehicle, a command value relating to longitudinal acceleration to be caused to the vehicle. During a time interval from before the vehicle reaches a near end of the curve, until the vehicle has approached the curve and traveled to a site having a constant or maximum curvature of the curve, the vehicle motion control arithmetic means computes a plurality of different negative longitudinal acceleration command values. Thus, even when there is no lateral motion, the vehicle motion control device accelerates/decelerates the vehicle while improving a driver's feeling of slowdown.