Abstract: Metabolonic study of sufu fermented by Mucor and Mucor- Lactobacillus rhamnosus GG strain( LGG)was conducted,using gas chromatography / mass spectrometry( GC / MS) to acquire the changes of the chemical components of sufu during the fermentation.85 compounds including amino acids,organic acids and sugars were identified and 33 of them were validated by authentic standards.The analysis revealed that sufu fermented with the assistance of LGG could produce higher content of amino acids such as alanine,glycine,serine,threonine and aspartate,thus enhance its taste of sweetness or palatable.Though profiles of compounds at different time under different fermentation indicated that the addition of lactobacillus could not accelerate fermentation of sufu,this work indicated that lactobacillus could be use to improve and optimize the fermentation of sufu.Besides,the study has demonstrated that metabolomic strategies could apply to optimize the fermentation process of sufu,as well as other traditional fermented foods.