The present invention provides a stereoselective synthesis method of lacosamide or an analogue thereof used as an anticonvulsant. The synthesis method of the present invention can synthesize lacosamide or an analogue thereof through a short reaction process in a higher yield compared to conventional synthesis methods, by using an aziridine-2-carboxylate derivative. The analogue of lacosamide may be beneficially used to screen for more effective medicinal materials, and further to produce novel pharmacologically active materials.본 발명은 항경련제로 사용되는 라코사마이드 또는 이의 유사체의 입체선택적 제조방법을 제공한다.