The present invention relates to a bearing structure with a close fit, which comprises a fan frame having a base and a shaft sleeve disposed vertically. The shaft sleeve has a receiving space in which a bearing set is disposed. At least one external ring is sleeved around the outer perimeter of the shaft sleeve and is disposed corresponding to the bearing set. Therefore, by means of the external ring, the close fit between the shaft sleeve and the bearing set is improved, which increases the assembly precision.