Abstract: In order to research the influence of the brewing process on the formation of soy sauce flavor, the headspace solid phase microextraction (HS-SPME) coupling was used. The composition and change of volatile aroma components in a fermentation process of a brand of soy sauce in Heilongjiang region were determined by GC-MS. The study found that 31 kinds of aroma components were detected in the fermentation process, including 3 kinds of alcohols, 4 kinds of aldehydes, 4 kinds of acids, 6 kinds of esters, 4 kinds of phenols, 3 kinds of furans and 7 kinds of other compounds. Further, four main aroma substances were determined by measuring the aroma activity values:1-octene-3-ol, phenylacetaldehyde, acetic acid, 4-vinylguaiacol;principal component analysis showed that the fermentation time was at 5~42 d, 1-octene-3-ol, acetic acid and 4-vinylguaiacol were characteristic components, and when the fermentation time was 42~59 d, and phenylacetaldehyde was the main component.