Fatty acid contents of peanut seeds (cultivar NC2) at three stages of maturity harvested between 1985 and 1987 from two soil types in St Vincent, Eastern Caribbean, were determined by gas-liquid chromatography. Oil from mature NC2 seeds grown in St Vincent contained more oleic and less linoleic acid than oil from mature NC2 seeds grown in North Carolina and Jamaica. With respect to soil types in St Vincent, seeds grown on volcanic clay loam contained more stearic, long-chain and total saturated fatty acids but less linoleic and total unsaturated acids than samples from volcanic sandy loam. As seeds progressed from intermediate through nearly-mature to mature stages, palmitic and linoleic acids (%) decreased while oleic acid increased. Also, irrespective of soil type and year, oleic acid (%) in the oil of mature seeds was 57 4 ± 0 77, suggesting that this value may be a useful index of seed maturity for the NC2 peanut cultivar grown in St Vincent.