A novel, to the best of our knowledge, method is proposed in this study to permit the controllable resolution of a micro-angle measurement by using a Michelson interferometer. The resolution of the proposed system can be adjusted by changing the distances between a pair of parallel mirrors. Through experiments, it was observed that as the distance was changed from 0 to 6 mm, the corresponding resolution was significantly altered from 22.88 to 14.02 µrad. Compared with other small angle measurement methods, the proposed method can realize the conversion of multiple measurement resolutions more easily and conveniently.