The genusJatropha holds great promise as a potential novel drug source because it have many useful activities and phytochemical constituents. This study evaluated the phytochemical composition, anticancer effects against HepG2 (Hepatocellular carcinoma cell line), and antimicrobial efficiency of methanol leaf extracts from Jatropha curcas L., Jatropha gossypifolia L., and Jatropha multifidia L. in vitro. Flavonoids, tannins, alkaloids, saponins, terpenes and sterols were detected in the methanol extracts of both J. curcas and J. gossypifolia. The leaf extract from J. curcas exhibited high effectiveness against the HepG2cell line, with a selective index of 2.04, as well as effective against Gram-positive and Gram-negative bacteria. Two fractions (JCF1 and JCF2) were collected after the crude methanol extract was purified from J. curcas using a silica gel column.  Gram (+ve) bacteria were the only ones susceptible to JCF1, but Gram (+ve) and Gram (-ve) bacteria were both susceptible to JCF2. Hexadecanoic acid (18.43%), anethole (18.28%), estragol (18.28%), oleic acid (13.67%), phytol (10.84%), and carvacrol (7.56%) were found to be the most abundant components of JCF1 in a Gas Chromatography–Mass Spectrum (GC-MS) analysis. In contrast, the most abundant chemical components of JCF2 were hexadecanoic acid (18.05 %), hexadecanoic acid methyl ester (9.50 %), octadecanoic acid methyl ester (3.29 %), anethole (3.1 %), estragole (3.1 %), thymol (1.61%), and carvacrol (1.61%).