A roller bearing cage includes ring portions and pillar portions extend in an axial direction to connect the ring portions and disposed along a circumferential direction to define pocket portions. The pillar portion includes a bent portion formed in the vicinity of an axial center of the pillar portion so as to protrude radially inwards of the ring portions. A ring portion thickness is larger than a bent portion thickness; a pillar end portion thickness is larger than the bent portion thickness; and the pillar end portion thickness is equal to the ring, portion thickness or more, where the ring portion thickness is a radial thickness of the ring portion; the bent portion thickness is a radial thickness of the bent portion; and the pillar end portion thickness is a thickness of a portion of the pillar portion connected to the ring portion and in the vicinity thereof.