Abstract: Determinations by Soxhlet extraction and GC (gas chromatography)were implemented on oil content and components of fatty acids fromnut kernels of 30 Carya cathayensis trees in the same stand located in Lin’an, Zhejiang province, sampled on July 23, August 1, August 16 and 31 of2014. Results showed that oil content increased significantly along with maturation of seeds, the average content was 9.87%, 38.30%, 72.06% and71.65% of samples with different dates. There was significant difference of oil content either among sampling dates or among individual trees. Themean content of main fatty acids in kernel, such as palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid ranged from 15.48% to4.57%, 2.38% to 1.50%, 20.45% to 66.01%, 45.24% to 21.48% and 8.49% to 1.54% respectively. Only the average content of oleic acid increasedgradually. The main saturated fatty acid in kernel was palmitic acid, and the main unsaturated one was oleic acid. The content of unsaturated fattyacids was always higher than that of saturated ones.