With the raw material of 7-Aminocephalosporanic acid (7-ACA) and paratoluensulfonyl chloride cefmetazole was synthesized.The new method has four steps and the total yield of four steps can be improved to 57%.Compared to the tradition synthesis method,the new route has advantages of few steps,high yield,stable intermediate and most importantly,the raw materials are inexpensive.So the new synthetic course and technics have definite practicality and extensive application in the industrial production.