A pneumatic tire comprising: a tread portion comprising a designated mounting orientation on a vehicle, an outboard tread edge (To) located on an outboard of the vehicle when the tire is mounted on the vehicle and an inboard tread edge (Ti) located on an inboard of the vehicle when the tire is mounted on the vehicle; the tread portion being provided with a circumferentially and continuously extending first main groove nearest to the outboard tread edge (To) and a circumferentially and continuously extending second main groove adjacent to the first main groove on the side of the inboard tread edge (Ti) to form an outboard middle land portion between the first main groove and the second main groove; the first main groove comprising first portions and second portions having a groove width (W1b) greater than that (W1a) of the first portions alternately in a circumferential direction of the tire; the outboard middle land portion being provided with a plurality of middle inclined grooves that are not directly communicated with neither the first main groove nor the second main groove, a plurality of outboard middle lug grooves connecting the second portions of the first main groove to the middle inclined grooves and inboard middle lug grooves connecting the middle inclined grooves to the second main groove; and the outboard middle lug grooves being arranged at different locations to the inboard middle lug grooves with respect to a circumferential direction of the tire; characterized in that each middle inclined groove comprises a first inclined middle element extending from an inner end on the side of the inboard tread edge (Ti) to an outer end on the side of the outboard tread edge (To) while increasing a groove width (W4a, W4b) toward the outer end and a second middle inclined element connecting the outer end of the first middle inclined element to one of the outboard middle lug grooves and having a groove width smaller than that of the first middle inclined element. a tread portion comprising a designated mounting orientation on a vehicle, an outboard tread edge (To) located on an outboard of the vehicle when the tire is mounted on the vehicle and an inboard tread edge (Ti) located on an inboard of the vehicle when the tire is mounted on the vehicle; the tread portion being provided with a circumferentially and continuously extending first main groove nearest to the outboard tread edge (To) and a circumferentially and continuously extending second main groove adjacent to the first main groove on the side of the inboard tread edge (Ti) to form an outboard middle land portion between the first main groove and the second main groove; the first main groove comprising first portions and second portions having a groove width (W1b) greater than that (W1a) of the first portions alternately in a circumferential direction of the tire; the outboard middle land portion being provided with a plurality of middle inclined grooves that are not directly communicated with neither the first main groove nor the second main groove, a plurality of outboard middle lug grooves connecting the second portions of the first main groove to the middle inclined grooves and inboard middle lug grooves connecting the middle inclined grooves to the second main groove; and the outboard middle lug grooves being arranged at different locations to the inboard middle lug grooves with respect to a circumferential direction of the tire; characterized in that each middle inclined groove comprises a first inclined middle element extending from an inner end on the side of the inboard tread edge (Ti) to an outer end on the side of the outboard tread edge (To) while increasing a groove width (W4a, W4b) toward the outer end and a second middle inclined element connecting the outer end of the first middle inclined element to one of the outboard middle lug grooves and having a groove width smaller than that of the first middle inclined element.