A motorcycle tire for running on rough terrain comprises a tread portion having a unidirectional tread pattern and provided with T-sided blocks having a top surface, a heel-side sidewall surface extending from a heel-side edge of the top surface, and a toe-side sidewall surface extending from a toe-side edge of the top surface. The heel-side sidewall surface has an inclination angle α of from 0 to 15 degrees. The toe-side sidewall surface has a radially outer region having a height of from 20 to 55% of the block height and inclined at an angle β of from 20 to 45 degrees. A radially inner region of the toe-side sidewall surface has: a central part inclined at the same angle β as the radially outer region; a pair of lateral parts located one on each side of the central part and having an inclination angle γ of from 0 to 15 degrees; and a pair of stepped parts extending between the lateral parts and the central part in a direction crosswise to the toe-side edge.