OBJECTIVE： To establish a method for the simultaneous contents determination of chloramphenicol and diphenhydramine hydrochloride in Chlorobenzene alcohol solution. METHODS： HPLC was performed on the column of Diamonsil C with mobile phase of phosphate buffer-acetonitrile （66.5 ∶ 33.5，V/V） containing 0.01 mol/L sodium heptane， column temperature was 35 ℃， flow rate was 1 ml/min， detection wavelength was 258 nm for diphenhydramine hydrochloride and 277 nm for chloramphenicol， the injection volume was 10 μl. RESULTS： The linear range was 34.8-139.4 μg/ml for chloramphenicol （r＝0.999 8） and 93.0-930.5 μg/ml for diphenhydramine hydrochloride （r＝0.999 8）； RSDs of precision， stability and reproducibility tests were lower than 2.0％； recoveries were 97.70％-104.02％ （RSD＝2.2％，n＝9） and 96.72％-101.72％（RSD＝1.6％，n＝9）. CONCLUSIONS： The method is specific， accurate with good precision， and suitable for the quality control of Chlorobenzene alcohol solution.