AbstractA lipase was isolated from a strain ofAspergillus flavus which attacked coconut kernel and oil with the liberation of free fatty acids. The enzyme was purified 109‐fold by ammonium sulphate precipitation, diethyl aminoethyl‐cellulose and Sephadex G‐200 chromatography. The optimum pH of the enzyme reaction was 6.2. The action of the enzyme on pure triglycerides was studied. The triglycerides of the shorter chain fatty acids were more rapidly hydrolyzed, while hydrolysis of tristearin was not detected under the conditions of assay. Km for trilaurin and trimyristin were 9.09×10−4 and 1.42×10−3 M, respectively. Para‐chloromercuricbenzoate was an inhibitor. Thin layer chromatography and gas liquid chromatography of the esterified products of enzymatic hydrolysis of coconut oil showed the presence of oleate, palmitate, myristate, laurate, caprate, caproate and caprylate but not stearate, although stearate was present in coconut oil.