A bearing device includes a shaft, a sleeve and a thrust plate. The shaft includes a convex portion having a curved surface provided at one end thereof. The sleeve includes an inner circumferential surface opposed to an outer circumferential surface of the shaft. The thrust plate includes a concave portion having a curved surface and arranged to make contact with the convex portion of the shaft. The shaft is supported by the sleeve and the thrust plate such that it may rotate about the central axis with respect to the sleeve and the thrust plate. A curvature radius of the concave portion is greater than a curvature radius of the convex portion but equal to or smaller than about 2.0 times of the curvature radius of the convex portion.