OBJECTIVE:To establish a HPLC method for determining the content of tinidazole in Yintal cleaning solu?tion.METHODS:Nova-Pak C 18 column was used.The mobile phase was methanol-water-glacial acetic acid(22∶78∶0.1). Internal standard was metronidazole.The UV detection wavelength was310nm.RESULTS:There was a good linerarity within the concentration range of20～100?g/ml of tinidazole in Yintai solution(r=0.9999).The average recovery was101.2%(n=5,RSD=1.16%).CONCLUSION:This method is simple,fast and accurate.