To clear the degradation regularity of propargite in apple, the liquid chromatography was applied to study the residue and degradation dynamics of 20% propargite agent in apple and soil. The results showed that the half life of propargite in apple was 14.6-36.2 d, which was 7.1-8.6 d in soil. When the dosage of 20% propargite agent was 1 500-3 000 ml/hm2, and the agent was sprayed for 2-3 times, the residues in apple and soil were less than 1.28 mg/kg. With comprehensive consideration on environmental safety, when 20% propargite agent was used to control apple mites, the recommended dosage was 1 500 ml/hm2, the agent could be sprayed for 2-3 times, and the safety interval was 14 d. To clear the degradation regularity of propargite in apple, the liquid chromatography was applied to study the residue and degradation dynamics of 20% propargite agent in apple and soil. The results showed that the half life of propargite in apple was 14.6-36.2 d, which was 7.1-8.6 d in soil. When the dosage of 20% propargite agent was 1 500-3 000 ml / hm2, and the agent was sprayed for 2-3 times, the residues in apple and soil were less than 1.28 mg / kg With comprehensive consideration on environmental safety, when 20% propargite agent was used to control apple mites, the recommended dosage was 1 500 ml / hm2, the agent could be sprayed for 2-3 times, and the safety interval was 14 d.