A thrust roller bearing (1, 1a, 71b, 71c, 71d) comprising: an annular cage (3, 72b) having a plurality of pockets (3a, 75a) arranged at a plurality of locations along a circumferential direction such that each of the pockets (3a, 75a) is oriented in a radial direction; a plurality of rollers (2, 73) held inside the respective pockets (3a, 75a) in a rollable manner; and at least one thrust race (4, 5, 74c, 74d, 74e, 74f, 74g) comprising an annular race portion (6, 8, 76a, 76b) on which a rolling surface of each of the rollers (2, 73) contacts in a rolling manner, and a cylindrical portion (7, 9, 77c, 77d) extending in an axial direction from a circumferential edge of the race portion (6, 8, 76a, 76b) toward a side on which the rollers (2, 73) are arranged, wherein protrusions (10, 10a, 91, 91a, 91b, 91c, 91d) are formed at a plurality of locations along the circumferential direction on the cylindrical portion (7, 9, 77c, 77d) of the thrust race (4, 5, 74c, 74d, 74e, 74f, 74g) such that each of the protrusions (10, 10a, 91, 91a, 91b, 91c, 91d) protrudes in the radial direction toward a side away from the race portion (6, 8, 76a, 76b) and has a width in the circumferential direction, characterized in that cutout portions (7b, 9b, 90, 90a) are formed at the plurality of locations along the circumferential direction on the cylindrical portion (7, 9, 77c, 77d) such that each of the cutout portions (7b, 9b, 90, 90a) is recessed in the axial direction from a distal edge of the cylindrical portion (7, 9, 77c, 77d) toward the race portion (6, 8, 76a, 76b), and the protrusion (10, 10a, 91, 91a, 91b, 91c, 91d) is provided at a portion closer to the race portion (6, 8, 76a, 76b) from a bottom edge of each of the cutout portions (7b, 9b, 90, 90a) such that the protrusion (10, 10a, 91, 91a, 91b, 91c, 91d) protrudes in the radial direction from the cylindrical portion (7, 9, 77c, 77d) toward the side away from the race portion (6, 8, 76a, 76b), the protrusion (10, 10a, 91, 91a, 91b, 91c, 91d) is configured to serve as a race-retaining locking portion to prevent the thrust race (4, 5, 74c, 74d, 74e, 74f, 74g) from moving out from a mating member (20, 21, 85, 85a, 83a) on which the thrust race (4, 5, 74c, 74d, 74e, 74f, 74g) is mounted, each of the cutout portions (7b, 9b, 90a) is formed in a portion of the cylindrical portion (7, 9, 77d) other than a base end portion of the cylindrical portion (7, 9, 77d) that lies closer to the race portion (6, 8, 76a), and an intermediate portion of the remaining uncut base end portion in the circumferential direction is bulged in the radial direction away from the race portion (6, 8, 76a) such that the bulged portion (10, 10a, 91b, 91c) forms the race-retaining locking portion. an annular cage (3, 72b) having a plurality of pockets (3a, 75a) arranged at a plurality of locations along a circumferential direction such that each of the pockets (3a, 75a) is oriented in a radial direction; a plurality of rollers (2, 73) held inside the respective pockets (3a, 75a) in a rollable manner; and at least one thrust race (4, 5, 74c, 74d, 74e, 74f, 74g) comprising an annular race portion (6, 8, 76a, 76b) on which a rolling surface of each of the rollers (2, 73) contacts in a rolling manner, and a cylindrical portion (7, 9, 77c, 77d) extending in an axial direction from a circumferential edge of the race portion (6, 8, 76a, 76b) toward a side on which the rollers (2, 73) are arranged, wherein protrusions (10, 10a, 91, 91a, 91b, 91c, 91d) are formed at a plurality of locations along the circumferential direction on the cylindrical portion (7, 9, 77c, 77d) of the thrust race (4, 5, 74c, 74d, 74e, 74f, 74g) such that each of the protrusions (10, 10a, 91, 91a, 91b, 91c, 91d) protrudes in the radial direction toward a side away from the race portion (6, 8, 76a, 76b) and has a width in the circumferential direction, characterized in that cutout portions (7b, 9b, 90, 90a) are formed at the plurality of locations along the circumferential direction on the cylindrical portion (7, 9, 77c, 77d) such that each of the cutout portions (7b, 9b, 90, 90a) is recessed in the axial direction from a distal edge of the cylindrical portion (7, 9, 77c, 77d) toward the race portion (6, 8, 76a, 76b), and the protrusion (10, 10a, 91, 91a, 91b, 91c, 91d) is provided at a portion closer to the race portion (6, 8, 76a, 76b) from a bottom edge of each of the cutout portions (7b, 9b, 90, 90a) such that the protrusion (10, 10a, 91, 91a, 91b, 91c, 91d) protrudes in the radial direction from the cylindrical portion (7, 9, 77c, 77d) toward the side away from the race portion (6, 8, 76a, 76b), the protrusion (10, 10a, 91, 91a, 91b, 91c, 91d) is configured to serve as a race-retaining locking portion to prevent the thrust race (4, 5, 74c, 74d, 74e, 74f, 74g) from moving out from a mating member (20, 21, 85, 85a, 83a) on which the thrust race (4, 5, 74c, 74d, 74e, 74f, 74g) is mounted, each of the cutout portions (7b, 9b, 90a) is formed in a portion of the cylindrical portion (7, 9, 77d) other than a base end portion of the cylindrical portion (7, 9, 77d) that lies closer to the race portion (6, 8, 76a), and an intermediate portion of the remaining uncut base end portion in the circumferential direction is bulged in the radial direction away from the race portion (6, 8, 76a) such that the bulged portion (10, 10a, 91b, 91c) forms the race-retaining locking portion.