Effects of Elaszym was tested on lipid metabolism and atherosclerosis in genetically restrictedovulator chickens with endogenous hyperlipidemia. A total of 12 eight month-old non-laying hens and 6 eight month-old roosters were used in this study. Non-laying hens were divided into 2 groups: Cont-NL group (without any treatment) and EL-NL group (With Elaszym). Elaszym was orally administered 3 times per week for 4 month. EL-NL group consisted of 6 non-laying hens, each of which received 5400 EL of Elaszym for the first 2 months, 1800 EL of Elaszym for the third month and 5400EL of Elaszym again for the last month of this study. Marked reductions in the serum triglyceride and cholesterol levels were noted in the EL-NL group compared to the Cont-NL group. The lipid and calcium content in the aortic tissue also decreased in the EL-NL group. The EL-NL group displayed a lesser degree of intimal thickening of the abdominal aortas than the Cont-NL group or roosters. Lipid-containing cells and extracellular lipid deposition were more prevalent in the aortas of the Cont-NL group than in those of the EL-NL group or roosters.