Determination of compositions and contents of fatty acids in vegetable oils，including tea seed oil，soybean oil，peanut oil，sunflower seed oil，corn oil and sesame oil，was performed by gas chromatography-mass spectrometry（GC-MS），to investigate the use of vegetable oil fatty acids indicators to distinguish different types of vegetable oils and classification possibilities.SPSS.19.0 statistical software was used to principal component analysis，cluster analysis and discriminant analysis.The fatty acids in six vegetable oils were investigated.The results indicated that the main compositions of vegetable oils were C16∶0，C18∶0，C18∶1 cis-9，C18∶2 cis-9，12 and C18∶3 cis-9,12,15，respectively.Total contents of five major fatty acids were 98.455%，97.586%，89.019%，97.378%，98.294% and 98.021% corresponding to the tea seed oil，soybean oil，peanut oil，sunflower oil，corn oil and sesame oil，respectively.The ratios of unsaturated and saturated fatty acids（U/S） were greater than 2.000 in six kinds of vegetable oils，in which the minimum value was 2.055 for peanut oil and the maximum value was 3.976 for tea seed oil.When this data set was used，in order to obtain the reduced number of principal components，the first three principal compounds were chosen（80.060% of the total variance） because the eigenvalues were higher than 1，and which explained the reason of higher percentage of variance than each original data.The first principal component explained the higher percentage of variance 35.853%，the second principal component explained the explained 23.847% and the third principal component explained 20.360%.The study established three discriminant functions and the discriminant function correlation coefficients were greater than 0.990.The initial classification accuracy and cross-validation accuracy of tea seed oil，soybean oil，peanut oil，sunflower oil，corn oil and sesame oil all reached to 100.0%.