A pneumatic tire comprising: on a tread surface, a plurality of circumferential main grooves extending continuously in a tread circumferential direction and a plurality of land portions defined by the circumferential main grooves and tread edges (TE1, TE2); wherein an intermediate land portion on a first side in a tread width direction, which is on the inside while the tire is mounted on a vehicle and which is adjacent to a tire equatorial plane side of an outermost circumferential main groove on the first side, is formed into blocks only by sipes extending in the tread width direction; wherein an intermediate land portion on a second side in the tread width direction, which is on the outside while the tire is mounted on a vehicle and which is adjacent to the tire equatorial plane side of an outermost circumferential main groove on the second side, is formed in a ribbed shape in which the land portion is not divided by grooves or sipes into blocks in the tread circumferential direction; wherein intermediate land portion lug grooves are formed in the intermediate land portion on the second side, with one end opening into the outermost circumferential main groove on the second side, and another end terminating within the intermediate land portion on the second side; and wherein lug grooves (41, 43) on a tread edge side are formed in outermost land portions in the tread width direction defined by the circumferential main grooves that are outermost in the tread width direction and the tread edges (TE1, TE2), with one end of each lug groove (41, 43) on the tread edge side opening to the tread edge (TE1, TE2) and another end terminating within the outermost land portion; wherein sipes (51, 55) are further formed in the outermost land portions; characterized in that an inward end in the tread width direction of each sipe (51, 55) terminates within the outermost land portion; and an extending length of the sipes formed in the outermost land portion on the first side is greater than an extending length of the sipes formed in the outermost land portion on the second side. on a tread surface, a plurality of circumferential main grooves extending continuously in a tread circumferential direction and a plurality of land portions defined by the circumferential main grooves and tread edges (TE1, TE2); wherein an intermediate land portion on a first side in a tread width direction, which is on the inside while the tire is mounted on a vehicle and which is adjacent to a tire equatorial plane side of an outermost circumferential main groove on the first side, is formed into blocks only by sipes extending in the tread width direction; wherein an intermediate land portion on a second side in the tread width direction, which is on the outside while the tire is mounted on a vehicle and which is adjacent to the tire equatorial plane side of an outermost circumferential main groove on the second side, is formed in a ribbed shape in which the land portion is not divided by grooves or sipes into blocks in the tread circumferential direction; wherein intermediate land portion lug grooves are formed in the intermediate land portion on the second side, with one end opening into the outermost circumferential main groove on the second side, and another end terminating within the intermediate land portion on the second side; and wherein lug grooves (41, 43) on a tread edge side are formed in outermost land portions in the tread width direction defined by the circumferential main grooves that are outermost in the tread width direction and the tread edges (TE1, TE2), with one end of each lug groove (41, 43) on the tread edge side opening to the tread edge (TE1, TE2) and another end terminating within the outermost land portion; wherein sipes (51, 55) are further formed in the outermost land portions; characterized in that an inward end in the tread width direction of each sipe (51, 55) terminates within the outermost land portion; and an extending length of the sipes formed in the outermost land portion on the first side is greater than an extending length of the sipes formed in the outermost land portion on the second side.