The present invention discloses salts and the amorphous form of a phenylalanine compound which is represented by the general formula (1). In the formula, the definition of M is same as the specification and M is sodium or potassium. The present invention also discloses a method for preparing the salts and the application of the salts. Said salt can be used to prevent or treat diseases associated with metabolic syndrome.本發明揭露一種通式(I)所示的苯丙胺酸類化合物的鹽及其無定形形式,式中M的定義同說明書。本發明還揭露一種該鹽的製備方法與應用。該鹽可以用於治療與代謝症候群相關的疾病。