This document specifies the principles, instruments and equipment, reagents and materials, determination steps, calculation of results, precision, etc. of the HPLC determination method for the main components of triamcinolone acetonide, diphenhydramine, and salicylic acid tincture. This document is applicable to the content determination of salicylic acid, triamcinolone acetonide acetate and diphenhydramine hydrochloride as the main components of triamcinolone acetonide diphenhydramine salicylic acid tincture.