To simplify a bearing assembly process and reduce cost by eliminating processes for pressing a bottom of a cage and tightening it additionally and to improve shape precision of the cage to improve bearing performance.

A cut-out part is not provided on outside diameter on a small collar e side of an inner ring B in "a section of 90°" and "a section of 270°" in a conventional example as shown in (b). On the contrary, a cut-out part L is provided on the outside diameter on the small collar e side of the inner ring B in "the section of 90°" and "the section of 270°" as shown in (c). Consequently, when the cage D covers the inner ring B in "a section of 180°" using "a section of 0°" of the inner ring as a fulcrum S, a tapered roller C can avoid interference with the outside diameter on the small collar e side of the inner ring B in "the section of 90°" and "the section of 270°".