目的　建立复方维甲酸凝胶中维甲酸和红霉素的分光光度测定方法。方法　采用一阶导数光谱法在 378nm处测定维甲酸的含量 ,用紫外分光光度法在 4 82nm处测定红霉素的含量。结果　维甲酸的平均回收率为 99.72 % ,红霉素的平均回收率为 99.4 5 %。结论　所建立的方法适用于复方维甲酸凝胶剂中维甲酸和红霉素的测定 Objective To establish a spectrophotometric method for the determination of retinoic acid and erythromycin in compound retinoic acid gel. Methods The first derivative method was used to determine the content of retinoic acid at 378 nm. The content of erythromycin was determined at 4 82 nm by UV spectrophotometry. The results of the average recovery of retinoic acid was 99.72%, the average recovery of erythromycin was 99.4 5%. Conclusion The established method is suitable for the determination of tretinoin and erythromycin in compound tretinoin gel