Moringa oleifera is a medicinal plant widely used in folkloric medicine of Africa and Asia for the treatment of ailments such as ulcer, wound, inflammation, heart problem, cancer, stroke, obesity, anaemia and liver damage. The chemical constituents of the methanolic extract of Moringa oleifera leaves and seeds were investigated using Gas chromatography-mass spectrometry. Sixteen chemical constituents were identified in the leaf methanolic extract; they are 9-octadecenoic acid (20.89%), L-(+)-ascorbic acid- 2,6- dihexadecanoate(19.66%), 14–methyl-8-hexadecenal (8.11%), 4- hydroxyl-4-methyl-2-pentanone (7.01%), 3-ethyl-2, 4-dimethylpentane (6.14%), phytol (4.24%), octadecamethyl-cyclononasiloxane (1.23%), 1, 2-benzene dicarboxylic acid (2.46%), 3, 4-epoxyethanone comprising (1.78%), N-(-1-methylethyllidene)-benzene ethanamine (1.54%), 4, 8, 12, 16-tetramethylheptadecan-4-olide (2.77%), 3-5-bis (1, 1-dimethylethyl)-phenol (2.55%), 1-hexadecanol (1.23%), 3, 7, 11, 15-tetramethyl-2 hexadecene-1-ol (1.17%), hexadecanoic acid (2.03%) and 1, 2, 3-propanetriyl ester-9 octadecenoic acid(1.23%). Five chemical constituents were identified in methanolic seed extract and they are oleic acid (84%), L-(+) - ascorbic acid- 2, 6-dihexadecanoate (9.80%), 9-octadecenoic acid (1.88%), methyl ester-hexadecanoic acid (1.31%) and 9- octadecenamide (0.78%). Results obtained showed that the methanolic leaf extract of Moringa oleifera has more chemical constituents than the seed with 9-octadecenoic acid (20.8%) as the highest in the leaf and oleic acid (84%) in the seed. These relatively diverse chemical constituents may be responsible for the medicinal properties of Moringa oleifera leaves and seeds.