Objective:To establish a method for the determination of related substances in Triamcinolone Acetonide and Econazole Nitrate Cream. Methods:HPLC was used, the chromatog. conditions were as follows:using octadecylsilane bonded silica gel as filler (kromasil 100-5 C18, 4.6 mm x 250 mm, 5 μm chromatog. column), column temperature was 45 °C;0.077% ammonium acetate buffer (adjusted pH value to 3.0 with phosphoric acid)-methanol (80:20) as mobile phase A, methanol acetonitrile (40:60) as mobile phase B, and the flow rate was 1.0 mL/min. The detection wavelength was 240 nm and 225 nm. Results:At 225 nm detection wavelength, the chromatog. peak of neg. sample, triamcinolone acetonide peak and impurity peak have no interference on the detection of econazole nitrate and its impurities. The resolution of econazole, Econazole impurity A, impurity B, impurity C, miconazole and unknown impurity peaks and adjacent chromatog. peaks in the test solution with known impurities meet the requirements;at the detection wavelength of 240 nm, the chromatog. peak of neg. sample and Yikang nitrate have no interference in the test solution with known impurities, triamcinolone acetonide, impurity A (triamcinolone), impurity B, impurity C and unknown impurity in the test solution with known impurities met the requirements. Conclusion:After the methodol. validation of the proposed related substances method, all indicators basically meet the requirements, indicating that the established method is suitable for the detection of related substances in triamcinolone Acetonide and Econazole Nitrate Cream.