Objective:To compare the quality differences in benzalkonium chloride samples from domestic and abroad to provide references for the quality standard revision for benzalkonium chloride in Chinese pharmacopoeia. Methods: The ratio of alkyl compo-nents was determined according to the method described in USP 38, and the total content of benzalkonium chloride was determined ac-cording to the method recorded in Chinese Pharmacopoeia (2015 edition) and USP 38, respectively. Results:According to the results of composition ratio of alkyl, the fraction defective of domestic samples and imported samples was 100% and 50%, respectively. The content difference between the values calculated by the methods in the two pharmacopoeias showed that the total content of domestic samples changed from 3. 86% to 4. 15%, and that of imported samples changed from 1. 15% to 3. 90%. Conclusion:There are sig-nificant differences in the quality of benzalkonium chloride between domestic samples and imported samples. It is recommended that the ratio of alkyl components should be supplemented in our pharmacopoeia referring to the method in USP 38 and the total content calcula-tion formula for benzalkonium chloride should be revised to improve the quality standard for benzalkonium chloride.