A spindle motor (50) is composed of a base (8), a sleeve (4) in cylindrical shape that is fixed on the base (8), a shaft section (1) inserted into a through hole (4b) of the sleeve (4) that is rotatable with respect to the base (8), a hub (7) that rotates together with the shaft section (1), a radial dynamic pressure bearing section (RB) formed between a bushing (13) and the sleeve (4), a flange section (4a) that protrudes in a radial direction on an outer circumferential section of the sleeve (4), a wall section (7a) in annular shape that protrudes with surrounding the sleeve (4), a thrust ring (3) that is fixed on an inner circumferential section of the wall section (7a) being adjacent to the flange section (4a) and the bushing (13) in an axial direction, and a seal plate (17 fixed on an outer circumferential section of the sleeve (4) with sandwiching the thrust ring (3) between the flange section (4a) of the sleeve (4) and the seal plate (17) in an axial direction. The spindle motor (50) is furnished with a first thrust dynamic pressure bearing section (SB1), which is formed between confronting surfaces (3a, 4a1) of the thrust ring (3) and the flange section (4a), and a second thrust dynamic pressure bearing section (SB2), which is formed between confronting surfaces (3b, 17a) of the thrust ring (3) and the seal plate (17).