To provide a pneumatic tire capable of ensuring driving performance after wear in addition to ensuring of the operation stability in a new product.

A U-shaped hidden groove 220 composed of a pair of narrow groove part 220A and narrow connection groove part 220B is passed through in a straight line in the tire width direction in the intermediate part in the tire width direction. In the new product, since the hidden groove 220 does not appear on the tread of a block 218, the block 218 keeps high stiffness without being divided, and handling performance is not decreased. When the block 218 is somewhat worn after driving, a part surrounded by a pair of narrow groove part 220A and narrow connection groove part 220B comes off from the block 218, a groove 222 having a water exhausting function appears in the tread of the block 218, and drop in wet performance after wearing is suppressed.