A radial sliding bearing provided with a sliding bearing (1), an inner ring (2), and an outer ring (3), the inner ring (2) is made of melt-cast metal and the outer ring (3) being constituted by an article molded from a resin composition, the inner ring (2) comprising a concavely curved surface (2a) on part of the axial direction of the outer circumference and a bearing hole (4) for mating with a support shaft on the inner circumference, the outer ring (3) having a convexly curved surface (3a) that contacts and slides against the concavely curved surface (2a) on the outer circumference of the inner ring (2) along part of the axial direction of the inner circumference, and the inner ring (2) and the outer ring (3) relatively rotating without contacting each other apart from the contact between the convexly curved surface and the concavely curved surface.