On the tread surface, land portions are defined by a pair of circumferential main grooves and divided, by circumferential narrow grooves 3 and multiple lateral grooves 4 connecting between the circumferential main groove and the circumferential narrow groove or between the circumferential narrow grooves, into block rows L each of which including polygonal blocks arranged in a tire circumferential direction, wherein a block arrangement having the polygonal blocks 5 arranged in a line-symmetric manner with respect to the tire equator as an axis of symmetry includes side regions R1, R2 facing each other across the tire equator C and displaced from each other in the tire circumferential direction by a phase difference of 0.2 to 0.4 times of a repetition pitch of a pattern of the block row.