the invention provides a method for manufacturing bearing assembly . the method comprises : coating a photoresist on an inner wall of a through hole of a bearing ; inserting an ultraviolet lamp having a transparent groove pattern thereon into through hole and performing exposure process so as to photosensitize the photoresist corresponding to the groove pattern ; removing the ultraviolet lamp and cleaning the photosensitized portion of the photoresist by developer ; etching the inner wall not covered with the photoresist by an etchant or forming a deposited layer on the inner wall not covered with the photoresist ; removing the photoresist reminding on the inner wall by a stripping agent so as to complete the method for manufacturing a dynamic bearing . the method is also proved to a surface of a shaft to manufacture the dynamic bearing .