Abstract:Fatty acids in the seed oil of Calophyllum polyanthum growing in Xishuangbanna, Yunnan Province were analyzed by means of GC-MS. Twelve fatty acids amounting to 99.39% of the total contents detected were identified. The main components were linoleic acid （38.75%）, palmitic acid （22.42%）, oleic acid （22.11%） and stearic acid （9.81%）.