A motorcycle tire for running on rough terrain comprises a tread portion provided with a plurality of blocks defining a block pattern. The blocks include center blocks whose centroids of their top surfaces are disposed within a center region of the tread portion defined as being centered on the tire equator and having a developed width of 25% of a developed tread width. The top surface of each of the center blocks is provided with an axially extending edge extending straight and parallel with the tire axial direction, and arc edges curved convexly toward the centroid of the top surface and disposed on both sides of the axially extending edge in the tire axial direction.