This study aimed to determine the bioactive component of gonads of the sea urchins Diadema setosum from Indonesian waters using Gas Chromatography Mass Spectrometry. Phytochemical test results qualitatively showed that the methanol extract of D. setosum gonads contained steroids-triterpenoids, saponins and alkaloids while the results of analysis using GC-MS illustrated that the largest contents were Hexadecanoic acid, methyl ester (29.53%) and Tetradecanoic acid, methyl ester (14.86%), followed by other components in small quantity including Methyl 13-methyltetradecanoate (0.55%), Pentadecanoic acid, methyl ester ss Methyl npentadecanoate (2.08%), Hexadecadienoic acid, methyl ester (0.48%), 9-Hexadecenoic acid, methyl ester (4.68%), Methyl 10-methyl-hexadecanoate (0.56%), Hexadecanoic acid (4.05%), Heptadecanoic acid, Methyl ester (4.17%), 6,9,12-Octadecatrienoic acid, Methyl ester (1.33%), 9-Octadecenoic acid (Z)-, Methyl ester (5.42%), Octadecanoic acid, Methyl ester (1.91%), 9,12-Octadecadienoic acid (Z, Z)-, Lineloic acid (8.58%), 5,8,11,14-Eicosatetraenoic acid, Methyl ester (3.21%), 9,12-Octadecadienoic acid, Methyl ester (4.71%), Cis-11Eicosenoic acid, Methyl ester (1.86%), (1S, 15S)-Byciclo [13.10] hexadecan-2-one (4.82%), Cholesta-3.5diene (0.67%), Cholest-5-en-3-ol (3β)-(4.20%). Components of the compound were reported to possess pharmacological function as antimicrobial, antifungal, antioxidant, anticancer, hipercholesterolemic agent, lubricant, antiinflammatory, nematicide, hepatoprotective, antihistaminic, pesticide, larvacidal activities, antiacne, anemiagenic, antiandrogenic, 5-alpha reduce inhibitor, antiarthritic and anticoronary properties. © RJPT All right reserved.