Abstract: OBJECTIVE To study antimicrobial effectiveness of phenol ear drops by the Chinese Pharmacopoeia (2015 Edition). METHODS Using Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Aspergillus and Candida albicans as test strains, the antimicrobial effectiveness test was carried out, to evaluate the survival of microorganisms at the different time. RESULTS The antimicrobial effectiveness of phenol ear drops met the requirements of the Chinese Pharmacopoeia (2015 Edition). CONCLUSION Phenol ear drops possess an intrinsic antimicrobial activity, so as to protect them from growth of microorganisms inadvertently introduced during or subsequent to the manufacturing process.