Upon incubation of [ 14C]oleoyl-CoA with either proplastids or microsomes prepared from soybean cell cultures, the following products were identified: 3-hydroxyoleate, a product of hydroxylase activity; Δ 2,9-octadecadienoic acid, a product of α, β-dehydrogenase activity; and Δ 9,12-octadecadienoic acid, the product of Δ 12-desaturase activity. The major products of linoleoyl-CoA metabolism were identified as: 3-hydroxylinoleate, a product of hydroxylase activity, and Δ 2,9,12-octadecatrienoic acid, a product of α, β-dehydrogenase activity; no product of Δ 15-desaturase activity was detected. Two minor products presumed to be geometric or positional isomers of Δ 2,9,12-18:3 were also detected. All products were characterized and identified by their thin-layer Chromatographic mobilities on 10% silver nitrate-silica gel G, and relative retentions on radio-gasliquid chromatography, by quantitative hydrogenation, by analysis of their products of permanganate-periodate oxidation, and by gas-liquid-mass spectrometric analysis.