Abstract: Forty-nine species of seed oils and 6 species of pulp oil from 11 genera were determined and the fatty acid composition of these oils was examined by gas liquid chromatography. The 11 genera belong to four tribes of subfamily Lauroideae. The major fatty acids of the seed oils from the tribe Cinnamomeae (Cinnamomum, Sassafras) and Litseeae ( Actinodaphne, Litsea, Neolitsea, Lindera, Laurus ) are saturated and unsaturated C10, C12, C14 acids except that of Neocinnamomum candatum (Nees) Merr. The seed oils from tribe Perseae (Machilus, Phoebe) and Cryptocaryeae (Cryptocarya) contain more than a trace of C10, C12, C14 acid. The major acids are 16:0 and unsaturated C18 acids. The component acids of pulp oils are different from that of the seed oils of the same species. The oils contain high proportion of palmitic, oleic and linoleic acid. The unsaturated C10, C12, C14 acids from seven seed oils (Litsea cubeba (L.) Pers., L. auriculata Chien et Cheng, Neolitsea chuii Merr, N. cambodiana Lec., Lindera rubronervia Gamble, L. praecox (Sieb. et Zucc.) Bl., L. reflexa Hemsl.) were separated and id- entified. They are cis-4-decenoic, cis-4-dodecenoic and cis-4-tetradecenoic acids. The three acids have not been found in the seed oils of any other plant family.

Key words: Lauraceae, Fatty acid