Abstract: An object is to provide a pneumatic tire which can achieve both irregular wear performance and wet and on-snow performances. A sipe 20, which extends in a zigzag shape in a tire axial direction and in a depthwise direction and which has a constant depth, is formed in a block 18. The sipe 20 is characterized in that a rigidity index F shown as follows differs in a sipe longitudinal direction. Rigidity index F=(1+?1)×(1+?2)×(1+?3) ?1: Sipe amplitude (mm) at block stepping surface. ?2: Sipe amplitude (mm) when viewing the block 18 orthogonal to the sipe 20 appearing at the stepping surface and in a cross-section in the depthwise direction. ?3: Amplitude of a ridgeline 22 extending in a depthwise direction of the sipe 20 when viewing a wall surface 20A of the sipe 20 in plan view.