n-Butyl chloroacetate was synthesized from chloroacetic acid and n-butanol in the presence of sulfamic acid used as catalyst. Experimental results showed that the yield of the ester could reach 86.1% when the mole ratio of n-butanol and was chloroacetic acid 1.4∶1, the amount of sulfamic acid used was 2.5% of the acid, reaction time was 2.5 h, and temperature was 130~139℃,demonstrating that sulfamic acid had good catalytic activity on synthesis of n-butyl chloroacetate, and the catalyst could be reused.