A shoulder land portion is constructed by block rows. Shoulder lateral grooves sectionalize the block rows. The shoulder lateral grooves extend along the tire width direction in such a manner as to cut across ground contact ends. A plurality of projections is provided on a wall surface of the shoulder lateral groove. The projections protrude out of the wall surface of the shoulder lateral groove without reaching a center of a groove width of the shoulder lateral groove and are lined up in a length direction of the shoulder lateral groove in an outside area in the tire width direction from the ground contact end. The projection is formed into a triangular shape or a trapezoidal shape in its plan view and is formed into a triangular shape or a trapezoidal shape in its front elevational view.