Provided is a substrate washing method in which the process time necessary to remove foreign matter on a substrate surface can be reduced and the surface can be prevented from being irregularly ground. The substrate washing method for washing a substrate (10) by grinding the same comprises a step of conveying a first substrate (10) and a second substrate, a step of grinding the first substrate (10) by a roller grinding stone (20), and a step of grinding the second substrate by the roller grinding stone (20). In the step of grinding the first substrate (10), the roller grinding stone (20) is slid in a direction (40) perpendicular to the conveyance direction (50) of the first substrate (10) and in the longitudinal direction of the roller grinding stone (20).