Eight indole alkaloids, melosines A–H, together with 13 known alkaloids, were isolated from the fruits of Melodinus cochinchinensis. The structure elucidation of isolated secondary metabolites was based on comprehensive spectroscopic data analysis. Melosine B showed moderate cytotoxic activity against five human cancer cell lines, HL-60, SMMC-7721, A-549, MCF-7, and SW480 with IC50 values ranging from 1.6 to 8.1 μM.