A rolling element retainer whose respective components are allowed to move angularly with respective to each other, and the engagement between the ring portion and the trough of the respective units is in form of the engagement of cylindrical ring portion with curved surface. By this way, the universal cornering ability of the rolling element retainer in accordance with the present invention can be substantially improved, which is able to slide smoothly along the circulation path of the linear transmission device without being warped and prolong the service life.