Effect of Ulva pertusa meal supplement to diet on improvement in lipid metabolism was determined in regard with plasma lipoprotein in black sea bream Acanthopagrus schlegeli, 1) At least 9 lipoproteins were electrophoretically detected. These lipoproteins were classified into albumin and globulin by salting-out. A lipoprotein classified as albumin having 150,000 in molecular weight was accounted for 57% in the total lipoproteins of control group. The Ulvu meal increased its proportion (67.6%). 2) Molecular weight of lipoproteins in globulin fraction was more than 700,000. While lipid class composition of albumin fraction did not changed, that of globulin fraction was highly variable under the influence of the dietary Ulva meal. 3) Wintering without feeding caused great changes in electrophoretic behavior of lipoprotein. However, no differences were found in lipoprotein composition between both groups after wintering. 4 The improvement of lipid metabolism by the Ulvu meal reflected on the plasma lipoprotein.