Roller bearing

A roller bearing comprising:

• an inner member having a raceway surface on an outer side;
• an outer member having a raceway surface on an inner side;
• a plurality of rollers disposed between the inner member and the outer member;
• and
• a rolling element-guided type of cage retaining the rollers,
• wherein the cage includes a plurality of pillars circumferentially equidistantly spaced apart from each other,
• wherein the rollers are disposed between respective circumferentially adjacent pairs of the pillars,
• wherein each of the pillars includes anti-separation portions disposed such that the anti-separation portions of each adjacent pair of the pillars that are opposed to each other via a corresponding one of the rollers prevent the corresponding one of the rollers from moving toward a cage radially outer side from between the adjacent pair of the pillars,
• wherein the pillars are shaped to come into contact with the rollers guiding the cage, on the anti-separation portions, and
• wherein in an imaginary plane orthogonal to center axes of the rollers guiding the cage by contact with the pillars, a contact angle defined by a first imaginary straight line connecting together a contact point between each of the anti-separation portions of the pillars and the corresponding one of the rollers, and the center axis of the corresponding one of the rollers, and a second imaginary straight line which is orthogonal to a radial straight line passing through the center axis of the corresponding one of the rollers, and which passes through the center axis of the corresponding one of the rollers is set to 20 degrees or more and 24 degrees or less.