The invention relates to a method for synthesizing high-purity benzoyl chloride, and belongs to the technical field of fine chemical engineering synthesis. The method comprises the following steps: (1) by taking benzoic acid and thionyl chloride as raw materials, under the action of a catalyst, heating, stirring and performing backflow reaction, and when a solution is clear and transparent, recycling redundant thionyl chloride to obtain obtaining a coarse benzoyl chloride product; (2) performing reduced pressure distillation on the obtained coarse benzoyl chloride product in a reduced pressure distillation tower, and collecting the fraction of 90-120 DEG C to obtain a finished benzoyl chloride product. The method is simple and convenient in process, high in reaction yield, high in security in the production process and good in product quality.