Abstract: To utilize the Pyracantha atalantioides fruits from Chongqing effectively,using Soxhlet extractor method to extract the oil,then the antioxidant capabilities of the oil were evaluated by DPPH free radical scavenging activity and ferric reducing antioxidant power( FRAP) assay. Last,the constituents of the methyl- esterification product of the oil were analyzed by gas chromatography- mass spectrometry( GC- MS),after methyl esterification of free fatty acids of the oil.From the above results,the yield of the oil was 1.1%,and the oil exhibited potent antioxidant activity by scavenging DPPH radicals and ferric reducing ability. Thirty compounds,which occupied 89.0% of total constituents,were identified. The dominant components were methyl palmitate( 20.3%),linoleic acid methyl ester( 18.7%),linolenic acid methyl ester( 22.8%) and stearic acid methyl ester( 4.6%),which illustrated the oil of the P.atalantioides fruits was rich in palmic acid,linoleic acid and linolenic acid.And also,the content of linolenic acid in the oil was higher than in the current other edible oils.So the oil of P.atalantioides fruits was worthy of development and utilization.