A tire comprising: a first circumferential groove arranged between a tread center portion and a shoulder portion; a second circumferential groove arranged on a tread center portion side of the first circumferential groove; a plurality of lateral grooves opened to the first circumferential groove and the second circumferential groove; and a plurality of blocks on a tread portion partitioned by the first circumferential groove, the second circumferential groove, and the plurality of lateral grooves, an air flow in a direction opposite to a tire rotating direction being generated in the first circumferential groove and the second circumferential groove during running of a vehicle; wherein each block of the plurality of blocks has: a first wall surface formed from a position where the lateral groove on a downstream side of the air flow is opened to the first circumferential groove, toward an upstream side of the air flow; a second wall surface formed from a position where the lateral groove on the downstream side of the air flow is opened to the second circumferential groove, toward the upstream side of the air flow; and a block corner portion formed at a position where the lateral groove on the upstream side of the air flow is opened to the first circumferential groove; and when the two blocks on the upstream side and the downstream side of the air flow adjacent in the tire circumferential direction are viewed, a virtual surface obtained by extending, on the downstream side of the air flow, the first wall surface of the block on the upstream side passes through a position in the first circumferential groove on the shoulder portion side of the block corner portion of the block on the downstream side and intersects with the block on the downstream side in the first circumferential groove; and a groove width of the second circumferential groove gradually increases toward the downstream side of the air flow at the second wall surface of the block. a first circumferential groove arranged between a tread center portion and a shoulder portion; a second circumferential groove arranged on a tread center portion side of the first circumferential groove; a plurality of lateral grooves opened to the first circumferential groove and the second circumferential groove; and a plurality of blocks on a tread portion partitioned by the first circumferential groove, the second circumferential groove, and the plurality of lateral grooves, an air flow in a direction opposite to a tire rotating direction being generated in the first circumferential groove and the second circumferential groove during running of a vehicle; wherein each block of the plurality of blocks has: a first wall surface formed from a position where the lateral groove on a downstream side of the air flow is opened to the first circumferential groove, toward an upstream side of the air flow; a second wall surface formed from a position where the lateral groove on the downstream side of the air flow is opened to the second circumferential groove, toward the upstream side of the air flow; and a block corner portion formed at a position where the lateral groove on the upstream side of the air flow is opened to the first circumferential groove; and a first wall surface formed from a position where the lateral groove on a downstream side of the air flow is opened to the first circumferential groove, toward an upstream side of the air flow; a second wall surface formed from a position where the lateral groove on the downstream side of the air flow is opened to the second circumferential groove, toward the upstream side of the air flow; and a block corner portion formed at a position where the lateral groove on the upstream side of the air flow is opened to the first circumferential groove; and when the two blocks on the upstream side and the downstream side of the air flow adjacent in the tire circumferential direction are viewed, a virtual surface obtained by extending, on the downstream side of the air flow, the first wall surface of the block on the upstream side passes through a position in the first circumferential groove on the shoulder portion side of the block corner portion of the block on the downstream side and intersects with the block on the downstream side in the first circumferential groove; and a groove width of the second circumferential groove gradually increases toward the downstream side of the air flow at the second wall surface of the block.