OBJECTIVE: To isolate and identify chemical constituents of Cassia alata. METHOD: Compounds were separated and purified by column chromatography with silica gel and Sephadex LH-20, elucidated by spectroscopic methods including 1D and 2D NMR, IR and MS techniques. RESULT: Twelve compounds were isolated from C. alata, which were identified as chrysoeriol (1), kaempferol (2), quercetin (3), 5,7,4'-trihydroflavanone (4), kaempferol-3-O-beta-D-glucopyranoside (5), kaempferol-3-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (6), 17-hydrotetratriacontane (7), n-dotriacontanol (8), n-triacontanol (9), palmitic acid ceryl ester (10), stearic acid (11), palmitic acid (12). CONCLUSION: Compounds 3-12 were isolated from C. alata for the first time.