OBJECTIVE:To prepare the compound tinidazole washing liquid and to establish the quality control method for this medicine.METHODS:Tinidazole and chloromycetin were taken as the chief components for the preparation of the washing liquid;the contents of the chief components were determined by the dual-wavelength spectrophotometric method.RESULTS:The linear ranges for the concentration determination of tinidazole and chloromycetin were6.4～12.8mg/L and8.0～16.0mg/L respectively;the average recoveries of tinidazole and chloromycetin were100.09%and100.00%respectively,the relative standard deviations(RSD)of which were0.17%and0.22%respectively.CONCLUSION:The preparation is simple in preparation,accurate in content determination,stable and reliable in quality.