A pneumatic tire, for which a mounting direction is designated when the tire is mounted on a vehicle, comprising: an annular-shaped tread portion extending in a tire circumferential direction; a pair of side wall portions disposed on both sides of the tread portion; and a pair of bead portions disposed on an inner side in a tire radial direction of the side wall portions, a first main groove that extends in the tire circumferential direction being provided in a center region of the tread portion, a second main groove that extends in the tire circumferential direction being provided in a region further to an inner side of the vehicle than a tire equatorial position of the tread portion, a distance from a center position of the first main groove to the tire equatorial position being set so as to be 6% or less of a half-width (TL/2) of a tire ground contact width, a distance from a center position of the second main groove to the tire equatorial position being set so as to be from 40% to 65% of the half-width TL/2 of the tire ground contact width, a first rib being defined further to the inner side of the vehicle than the second main groove, a second rib being defined between the second main groove and the first main groove, and a third rib being defined further to an outer side of the vehicle than the first main groove, and a plurality of first lug grooves, a plurality of second lug grooves, a plurality of third lug grooves, a plurality of fourth lug grooves, and a plurality of fifth lug grooves being provided in the tread portion, each of the first lug grooves being positioned between a ground contact edge on the inner side of the vehicle and the second main groove and both ends thereof being closed within the first rib, one end of each of the second lug grooves being communicated with the second main groove and the other end thereof being closed within one of the first rib and the second rib, one end of each of the third lug grooves being communicated with the first main groove and the other end thereof being closed within one of the second rib and the third rib, each of the fourth lug grooves being positioned between a ground contact edge on the outer side of the vehicle and the first main groove and both ends thereof being closed within the third rib, and each of the fifth lug grooves being positioned between the ground contact edge on the outer side of the vehicle and the fourth lug groove and both ends thereof being closed within the third rib. an annular-shaped tread portion extending in a tire circumferential direction; a pair of side wall portions disposed on both sides of the tread portion; and a pair of bead portions disposed on an inner side in a tire radial direction of the side wall portions, a first main groove that extends in the tire circumferential direction being provided in a center region of the tread portion, a second main groove that extends in the tire circumferential direction being provided in a region further to an inner side of the vehicle than a tire equatorial position of the tread portion, a distance from a center position of the first main groove to the tire equatorial position being set so as to be 6% or less of a half-width (TL/2) of a tire ground contact width, a distance from a center position of the second main groove to the tire equatorial position being set so as to be from 40% to 65% of the half-width TL/2 of the tire ground contact width, a first rib being defined further to the inner side of the vehicle than the second main groove, a second rib being defined between the second main groove and the first main groove, and a third rib being defined further to an outer side of the vehicle than the first main groove, and a plurality of first lug grooves, a plurality of second lug grooves, a plurality of third lug grooves, a plurality of fourth lug grooves, and a plurality of fifth lug grooves being provided in the tread portion, each of the first lug grooves being positioned between a ground contact edge on the inner side of the vehicle and the second main groove and both ends thereof being closed within the first rib, one end of each of the second lug grooves being communicated with the second main groove and the other end thereof being closed within one of the first rib and the second rib, one end of each of the third lug grooves being communicated with the first main groove and the other end thereof being closed within one of the second rib and the third rib, each of the fourth lug grooves being positioned between a ground contact edge on the outer side of the vehicle and the first main groove and both ends thereof being closed within the third rib, and each of the fifth lug grooves being positioned between the ground contact edge on the outer side of the vehicle and the fourth lug groove and both ends thereof being closed within the third rib.