Abstract: In order to study the changes of aroma components in the process of pickling Zhacai(low salt)in mechanical dehydration,the headspace solid phase microextraction combined with gas chromatography-mass spectrometry(GC/MS)was used to determine the aroma components of low salt Zhacai in different periods. The results showed that the main aroma components of Zhacai pickling were isothiocyanates and aldehydes,which were directly related to the glucosinolates decomposition and microbial fermentation in the process of pickling. The relative content of isothiocyanates in Zhacai pickling reached 22.33% after 6 d of pickling,and then decreased with the pickling process. Thiodiglycol was the main aroma component of alcohols and aldehydes. The relative content of alcohols and aldehydes increased and then decreased and the relative content reached 24.85% at 21 d. The changes of esters and heterocyclic compounds were more complex;the types and relative contents of acid aroma components showed a general downward trend;alkanes and other aroma components were mainly 2,5-dimethyl octane and cis-4-methyl-2-pentene,respectively.