The invention discloses a novel method for synthesizing cefpirome sulfate serving as a cephalosporin antibiotic, and belongs to the field of medicinal chemistry. The method comprises the following steps of: performing substitution reaction on (6R,7R)-3-(acetoxyl)methyl-7-2-amino-4-thiazolyl-(methoxyimino)acetylamino-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-formic acid serving as an initial raw material and 2,3-cyclopentene pyridine, and performing salt forming reaction on a reaction product and sulfuric acid to obtain the cefpirome sulfate product. By the method, three-step reaction in the step (1) is continuously performed in the same reactor; and an expensive silicon reagent is not used, so that production cost is reduced, and the synthesis process is simple, convenient to operate and favorable for industrial production.