An edge trimming method for cutting an outer peripheral portion of a workpiece having a chamfered part on the outer peripheral portion. The method includes a cut in step of relatively moving a rotating cutting blade and a chuck table to cause the blade to cut into the outer peripheral portion, a cutting step of, after the cut in step, rotating the chuck table and causing the outer peripheral portion to be cut, to form an annular step, and a moving step of, after the cutting step, moving the blade in a direction of its axis of rotation to form another annular step adjacent to the first-mentioned annular step. The cut in, cutting, and moving steps are repeated in this order, and a stepped oblique region is formed on the outer peripheral portion, with a thickness increasing from an outermost peripheral edge toward an inner side of the workpiece.