To improve driving force and the like on a road surface having different soils in a depth direction.

A pneumatic tire 1 for irregular ground traveling which is 10 to 70% in a land-sea ratio is provided with a plurality of blocks in a tread portion 2. In that case, on a tire cross-section including a ire rotating shaft in a normal state, the tread portion 2 includes a plurality of blocks 10 bulging at 10.0 to 35.0 mm height in a normal direction from a base surface 9 connecting outer ends 3t of a side wall portion 3 and having an outer surface made from a smooth arc. In that case, the block 10 includes a high block 11 having the maximum height, and a low block 12 having lower height than the height block 11. Therefore, a ground surface 12c of the low block 12 is provided on an inner side in a tire radial direction rather than a virtual tread surface VT made from a smooth arc Ct which passes a height position of the high block 11 and is line symmetric about tire equator.

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