In order to identify species difference of lipoprotein lipases (LPL) between chickens and rats, possible modification of purification of the LPLs was introduced. Crude enzyme prepared from acetone powders of adipose tissue in both the species was added with glycerol to give 30% in final concentration, and chromatographed on Heparin-Sepharose 4 B, Hydroxyapatite and Con A-Sepharose 4 B column. The fraction obtained by elution through the Con A-Sepharose 4 B was shown to yield single band on electrophoresis in sodium dodecyl sulfate (SDS-PAGE). Thus LPLs were purified by 2, 500 and 1, 400 folds compared to the original activity in chickens and rats, respectively, with no contamination of antithrombin III. These results showed that the modified purification procedure is effective in identification of species difference in LP