Abstract: In order to clarify the differences in flavor quality and identify the characteristic volatile flavor compounds of purple onion from different geographical origins, with purple onions from four different regions in China as research objects, HS-SPME-GC-MS method combined with principal component analysis and partial least squares discriminant analysis was applied in the analysis of volatile flavor compounds and the identification of the characteristic volatile flavor compounds. The results showed that a total of 45 volatile flavor compounds including 27 sulfur compounds, 3aldehydes, 1 ketone and 14 other compounds were detected in the test purple onion samples. The major differential flavor compounds in purple onion from Hebei, Shandong, Yunnan and Gansu provinces were determined as dipropyl trisulfide,（E）-1-（prop-1-en-1-yl）-2-propyldisulfane,（Z）-1-（prop-1-en-1-yl）-2-propyldisulfane, 2-ethyl-trans-2-butenal,（E）-2-butenal diethyl acetal, 2-methyl-2-pentenal, and 1-propanethiol. In terms of the overall flavor quality, the purple onion from Gansu was considered to be superior to the other samples.