Abstract: Seven species of seedoils from Trichosanthes have been ex-amined about its fatty acid compositions by GC, UV, and IRetc.. It has been found that they all contain an unusual fatty acid constituent punicic acid which seldom occurs in the nature and are rich in it. Therefore we have reason to suppose that maybe punicic acid occurs in the seedoils of whole Trichosanthes genus as a common chemical composition.