Pneumatic Tire

A pneumatic tire, comprising:

• at least three main grooves that extend in a tire circumferential direction on a tread portion;
• and
• a plurality of rows of land portions that extend in the tire circumferential direction and are defined by these main grooves, wherein
• a plurality of compound grooves, each including a lateral groove having a first end that communicates with a main groove on one side thereof and a second end that terminates inside the land portion, and further including a sipe that extends from the second end of the lateral groove to the main groove on the other side thereof, are formed at an interval in the tire circumferential direction in at least one row of the land portions positioned inside a center region defined between the main grooves furthest on the outside;
• the compound grooves are disposed so that an opening direction of the lateral grooves relative to the main grooves alternatingly reverses in the tire circumferential direction;
• the lateral grooves each include a broad width portion that opens to the main groove and extends at a constant groove width, and a narrow width portion positioned between the broad width portion and the sipe and extends at a constant groove width narrower than that of the broad width portion;
• and
• a ratio Wa/Wb of a groove width Wa of the broad width portion to a groove width Wb of the narrow width portion is within a range of from 1.2 to 3.0, and a ratio Wb/Ws of the groove width Wb of the narrow width portion to a groove width Ws of the sipe is within a range of from 1.2 to 5.0.