A pneumatic tire having a specified mounting direction with respect to a vehicle, the pneumatic tire comprising: an inner main groove on a vehicle inner side and an outer main groove on a vehicle outer side, which are provided in a tread surface on both sides of a tire equator S; wherein the inner main groove and the outer main groove extend continuously in the circumferential direction; and an inner circumferential direction groove that is provided in the tread surface between the inner main groove and an inner tread surface end and that has a smaller groove width than the inner main groove and the outer main groove, wherein an inner side land portion that extends continuously in a circumferential direction is defined between the inner main groove and the inner circumferential direction groove, and an inner shoulder land portion that extends continuously in the circumferential direction is defined between the inner circumferential direction groove and the inner tread surface end, and wherein, if L is a distance from a side wall of the inner main groove to the inner tread surface end, the side wall being the one which is closer to the inner tread surface end, M is the groove width of the inner circumferential direction groove, and N is a width of the inner side land portion, a value of the groove width M divided by the distance L is in a range of 0.020 to 0.100, and a value of the width N divided by the distance L is in a range of 0.350 to 0.450, wherein: the inner main groove is configured from a pulsating groove whose groove width B repeatedly and continuously increases and decreases at a fixed pitch P in the circumferential direction so that the width of the inner side land portion increases and decreases at the fixed pitch P in the circumferential direction, and side transverse grooves that extend from the inner circumferential direction groove toward narrowest width positions U of the inner main groove and terminate before reaching the inner main groove are provided in the inner side land portion. an inner main groove on a vehicle inner side and an outer main groove on a vehicle outer side, which are provided in a tread surface on both sides of a tire equator S; wherein the inner main groove and the outer main groove extend continuously in the circumferential direction; and an inner circumferential direction groove that is provided in the tread surface between the inner main groove and an inner tread surface end and that has a smaller groove width than the inner main groove and the outer main groove, wherein an inner side land portion that extends continuously in a circumferential direction is defined between the inner main groove and the inner circumferential direction groove, and an inner shoulder land portion that extends continuously in the circumferential direction is defined between the inner circumferential direction groove and the inner tread surface end, and wherein, if L is a distance from a side wall of the inner main groove to the inner tread surface end, the side wall being the one which is closer to the inner tread surface end, M is the groove width of the inner circumferential direction groove, and N is a width of the inner side land portion, a value of the groove width M divided by the distance L is in a range of 0.020 to 0.100, and a value of the width N divided by the distance L is in a range of 0.350 to 0.450, wherein: the inner main groove is configured from a pulsating groove whose groove width B repeatedly and continuously increases and decreases at a fixed pitch P in the circumferential direction so that the width of the inner side land portion increases and decreases at the fixed pitch P in the circumferential direction, and side transverse grooves that extend from the inner circumferential direction groove toward narrowest width positions U of the inner main groove and terminate before reaching the inner main groove are provided in the inner side land portion. the inner main groove is configured from a pulsating groove whose groove width B repeatedly and continuously increases and decreases at a fixed pitch P in the circumferential direction so that the width of the inner side land portion increases and decreases at the fixed pitch P in the circumferential direction, and side transverse grooves that extend from the inner circumferential direction groove toward narrowest width positions U of the inner main groove and terminate before reaching the inner main groove are provided in the inner side land portion.