Reductions of the side force and the connected yawing moment are of significance for driving stability under cross wind. This paper shows the suitable body shape under unsteady cross wind for reducing side force and yawing moment. Numerically, the shape changes such as rounded and/or cut off corners and patterned indented side surface under steady cross wind are evaluated, using k-s model. The adequate shapes from the numerical data are experimentally validated under steady and unsteady cross wind in a wind tunnel. Flow structure and, side force and yawing moment are examined by High-speed PIV and a three-component load cell, respectively.