The synthesis process of(1R,2S)-2-fluorocyclopropylamine p-toluenesulfonate is studied.(1S,2S)-2-fluorocyclopropanecarboxylic acid is synthesized from butadiene through cyclization,oxidation,reduction,resolution,and other reactions,and the optimal reaction conditions are determined.Further,(1R,2S)-2-fluoro-cyclopropylamine p-methanesulfonate,the target product,is obtained with a total yield of 75%.