Disclosed is a substrate treating apparatus including a treatment solution dispenser supplying a treatment solution on a substrate, a transporting unit transporting the substrate, and a controller controlling the transporting unit so that the substrate is transported in an inclined position. The substrate is inclined sideways through a rotation with respect to an axis extending parallel to a transportation direction of the substrate. The rotation may be made in both directions in an alternating manner. The apparatus is useful for treating the substrate uniformly regardless of substrate size.