Abstract: Objective：To establish the method for the determination of diphenhydramine hydrochloride in Shexiang guanjie zhitong plaster， and to evaluate the quality of 87 batches of Shexiang guanjie zhitong plaster produced by 3 manufactures. Methods：HPLC method was established. The determination was performed on Hypersil Gold C18(250 mm×4.6 mm，5 μm)column with the mobile phase consisted of methanol-1% ammonium sulfate(47∶53， V/V) at the flow rate of 1.0 mL·min-1. The column temperature was set at 35 ℃， the detection wavelength was 210 nm. With the content data of 87 batches of samples as the index， histogram， box chart and three-dimensionalscatterplot are drawn， and adopt those to evaluate the quality. Results：The results of methodological investigation were in line with the requirements of the general principles stated in 2020 edition of Chinese Pharmacopoeia(part Ⅳ). The linear range of diphenhydramine hydrochloride injection volume is 0.200 4-5.010 μg(r=1.000 0)， the average recovery was 94%， RSD=1.9%. Thecontent of diphenhydramine hydrochloride in 87 batches of samples from 3 manufacturers were 1.22-8.74 mg·100 cm-2.Conclusion：The established method for the determination of diphenhydramine hydrochloride in Shexiang guanjie zhitong plaster is accurate and precise， and can be used for its quality control. Some manufacturers should pay attention to optimizing production process parameters and strengthen quality control.

Key words: font-size:medium, ">Shexiang guanjie zhitong plaster Diphenhydramine hydrochloride； Content determination； Quality evaluation