Abstract: Wine mash fermented from grape pomace was used for acetic acid fermentation in brewing grape vinegar, and the dynamic changes of the chemical composition in the fermentation process was analyzed by GC-MS, amino acid analyzer and atomic absorption spectrographic analyzer. The results showed that the grape vinegar and wine mash contains similar types of aroma components, mainly esters and alcohols (specifically, monoethyl succinate and phenylethyl alcohol) . On the other hand, the type and content of amino acids showed significant difference between wine mash and grape vinegar, with 15 amino acids in wine mash and 5 in grape vinegar.The contents of 8 metal elements tested in this study showed little difference between wine mash and grape vinegar.