We have isolated the fetuin from sera of newborn calves by ethanol fractiona-tion in the presence of zinc and barium ions. Prepared fetuin was examined with polyacrylamide gel electrophoresis at pH 8.3 in Tris-HC1 buffer

a broad band stained strongly was observed corresponding to the a-globulin position

and another small narrow band was appeared

which migrate slowly and was stained very lightly. Estimated with sephadex G-200 gel filtration

the apparent molecular weight is 117

489. The hexose content of fetuin is 8.07%

and the sialic acids is 8.65% as expressed by percentage of deionized

moisture-free protein. All the parameters mentioned above were in good agreement with previous reports in the literatures. The yield of fetuin after dialysis and lyophilization was 300mg per 100ml of serum approximately. From this study it is concluded that the fetuin prepared by alcohol-metal ion fractionation from newborn calf serum is very pure

and the newborn calf serum is good source for the isolation of fetuin

when the fetal serum of calf is not available