Abstract: To understand the volatile flavor compounds in raw vegetables and conduct comparative analysis, the volatile substances of four types of raw vegetables, namely Mesembryanthemum crystallinum, chrysanthemum, edible Andrographis paniculata, and head lettuce, were determined using solid-phase microextraction combined with gas chromatography-mass spectrometry（SPME-GC-MS）. The relative content of each substance was calculated using area normalization method, and a comprehensive evaluation was conducted using the method of principal component analysis（PCA）. The results showed that a total of 10 major categories of volatile substances were detected in these four vegetables, with higher levels of aromatic compounds in Mesembryanthemum crystallinum and head lettuce, higher levels of aldehydes in chrysanthemums and edible Andrographis paniculata, and higher levels of alcohols in all four vegetables. There are 57 main volatile substances in two or more types of vegetables, and 7 main volatile substances in all four types of vegetables. There are 14 key flavor substances, and because each vegetable contains different key flavor substances, its aroma and flavor were also different. The PCA results showed that there were two main components that can be used as effective components for differentiation, indicating significant differences in volatile substances in Mesembryanthemum crystallinum, chrysanthemums, edible Andrographis paniculata, and head lettuce. The research results can provide reference for the processing, development, and application of the four types of raw vegetables.

Key words: raw vegetables, solid-phase microextraction, gas chromatography-mass spectrometer, volatile substances, principal component analysis