Objective:To establish an HPLC method for the determination of methoxsalen and dexamethasone acetate in compound methoxsalen lotions. Methods:An HPLC method was used. The determination was performed on a Sunfire C18 (250 mm × 4. 6 mm,5μm ) column with the mobile phase of acetonitrile-water ( 60∶40 ) at the flow rate of 1. 0 ml·min-1 . The column temperature was kept at 30℃, the detection wavelength was set at 240nm and the injection volume was 20μl. Results:Methoxsalen and dexamethasone acetate showed good linear relationship within the range of 12.71-101.68 mg·L-1(r=0.999 9) and 10.03-80.25 mg·L-1(r=0. 999 7) with the average recovery of 99. 32%(RSD=0. 11%, n=9 ) and 99. 63%(RSD=0. 20%,n=9) , respectively. Conclu-sion:The method is simple, accurate and repeatable, and suitable for the determination of methoxsalen and dexamethasone acetate in compound methoxsalen lotions.