The medicinally important Khaya senegalensis is a large tree (up to 35m in height) in the family Meliaceae. The stem bark and leaves have been widely used in African system of medicine against many human disorders. The leaves are used against diarrhea and bacterial infections. Khaya senegalensis seed oil was studied by GC-MS. The oil was also evaluated for antimicrobial activity. Twenty three constituents were detected by GC-MS analysis. Major constituents are: 9-octadecenoic acid (Z) - methyl ester (47.43%); methyl stearate (18.86%); hexadecanoic acid, methyl ester (14.19%); 9, 12-octadecadienoic acid methyl ester (8.26%) and eicosanoic acid methyl ester (3.45%). In the cup plate agar diffusion bioassay, the oil showed good activity against G+ve Staphylococcus aureus.