A needle roller and cage assembly include a cage having a width larger than a diameter thereof. Pillar sections of the cage each include roller retaining portions on radially inner and outer sides with respect to a roller pitch circle diameter and an oblique portion through which the roller retaining portions are continuous with each other. The oblique portion includes a first relief portion formed therein, for avoiding interference with a needle roller. The adjacent pillar sections form a pocket having a rectangular shape therebetween. The pocket includes a second relief portion in each of four corners thereof. The second relief portion extends in the axial direction of the cage from a position at which a short side of the pocket is elongated in a circumferential direction of the cage to an outer end of the roller retaining portion on the radially outer side.