A spindle motor comprises a central shaft, a hub rotatable about the shaft and having a central bore which is open at one end, a first bearing fitted in the bore to surround the shaft, a second bearing disposed within the bore to surround the shaft and axially spaced from the first bearing to be positioned closer to the open end of the bore, and an auxiliary bush fitted in the bore to fittingly receive the second bearing. The bush has an inward flange axially interposed between the first and second bearings. The flange provides a first surface in face-to-face contact with an outer race of the first bearing. The flange further provides a second surface parallel to the first surface and in face-to-face contact with an outer race of the second bearing.