To provide a thrust roller bearing, in which a cage and bearing ring is not separated even if vibrations or impacts act thereon.

In a circumferential wall part 7 of a bottomed cylindrical bearing ring 3, a projection part 8 disposed to a part at a predetermined angular range of a whole circumference is bent inward in a radial direction to form a bent part 9. At a position symmetric with respect to an axis 3a of the bearing ring 3 and on a straight line dividing the predetermined angular range into two sections, a caulking part 11 having circumferential length shorter than the bent part 9 is formed. Each tip end of the bent part 9 and the caulking part 11 is arranged inside in the radial direction from the outer circumferential edge part of the cage 2, so as to prevent the cage 2 from being pulled out of the opening of the bearing ring 3.