Abstract: AIM:To study the chemical constituents from the seeds of Griffonia simplicifolia Baill.METHODS:The chemical constituents were isolated and purified by a combination of chromatographic materials including silica gel,Sephadex LH-20,and preparative TLC.Their structures were elucidated on the basis of MS and NMR data analysis.The cytotoxic activities were evaluated against HepG2 cancer cell line using the MTT colorimetric method.RESULTS:A new -carboline alkaloid,griffonine(1),together with seven known alkaloids,hyrtioerectine B(2),3-carboxy-6-hydroxy--carboline(3),hyrtiosulawesine(4),5-hydroxyindole-3-carbaldehyde(5),5-hydroxy-3-(2-hydroxyethyl) indole(6),trigonelline(7),and 5-hydroxytryptamine(8) were isolated and identified.Alkaloids 1,2 and 4 showed growth inhibitory effects on the HepG2 cell line with IC50 values of 23.5,9.6 and 19.3 molL-1,respectively.CONCLUSION:Alkaloid 1 is new and was named griffonine.Alkaloids 2-7 were isolated from this plant for the first time.Alkaloids 1,2 and 4 were potentially cytotoxic.