Abstract: To study the fat content and fatty acid composition characteristics of different walnut varieties in Jinzhong Prefecture of Shanxi, and provide a basis for the cultivating, breeding, processing and utilization of walnut, the total fat content and fatty acid composition of 37 walnut varieties (Juglans regia L.) were analyzed by Soxhlet extraction and gas chromatography, and the data were calculated by variation analysis, correlation analysis, path analysis, cluster analysis and principal component analysis. The results showed that: (1) the total fat content of the 37 walnut varieties ranged from 56.8% to 70.88%, with an average of 65.78%; palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid were the major fatty acids, and the variation coefficient of oleic acid was the highest while that of linoleic acid was the lowest; (2) the composition of different fatty acids were all positively correlated with the total fat content, of which the linoleic acid and the total fat content were highly and significantly correlated, while the palmitic acid and the total fat content were significantly correlated; (3) the oleic acid had the maximum direct effect on total fat content, but the palmitic acid had the opposite effect; (4) the main information of fatty acid composition could be presented by a linear combination of the various compositions; (5) the 37 walnut varieties could be divided into“high oil content with high linolenic acid”variety group and“low oil content with high oleic acid”variety group.