Seed oils of ten leguminous tree crops were investigated for their fatty acid composition. Saturated acid components of the leguminous seed oils analysed revealed that low molecular weight acids (capric and lauric) did not commonly occur. On average, palmitic acid (19·4 ± 10·6) was the only major saturated acid present. However, within the subdivision Mimosoideae stearic acid content was slightly higher than in the subdivision Caesalpinoideae. Two members of the subdivision Mimosoideae— Tetrapleura tetraptera (13·9%) and Parkia clappertoniana (19·7%)—showed unusually high levels of behenic acid (22·0). Lignoceric acid (24·0) was not detected in any of the oils analysed. The major unsaturated acids in the seed oils of the leguminous crops investigated were oleic and linoleic acids, both comprising about 68·3% of the component acids. All members except P. africana (Mimosoideae) and Pterocarpus osun (Papilionaceae) were richer in linoleic acid than in oleic acid. Linoleic acid even comprised more than 50% of the component fatty acids in the seed oils of Adenanthera pavonina, T. tetraptera, D. oliverii and Bauhinia monandra. Very low levels of linolenic acid were detected in all the leguminous seed oils investigated. The nutritional implications of the component fatty acids are discussed.