PROBLEM TO BE SOLVED: To provide a fatty acid composition improver with which proportions of docosahexaenoic acid (DHA) and arachidonic acid (AA) are increased, and to provide food and drink for improving fatty acid composition or feed which is blended with the fatty acid composition improver.SOLUTION: Metabolism from α-linolenic acid of vegetal oil origin to DHA is enhanced by ingesting phosphatidylethanolamine and sphingomyelin, and a DHA content and an amount of AA in a living body increase.【課題】ドコサヘキサエン酸(DHA)およびアラキドン酸(AA)比率を増加させる脂肪酸組成改良剤、およびこの脂肪酸組成改良剤を配合した脂肪酸組成改良用飲食品または飼料の提供。【解決手段】ホスファチジルエタノールアミンとスフィンゴミエリンを摂取することにより、植物性油脂由来のα-リノレン酸からDHAへの代謝が亢進され、生体内のDHA含量およびAA量が増加する。【選択図面】なし