Abstract: Change rules of main nutritional components were researched during gear- variable temperature fermentation process. 17 samples were selected on the key time points. Main components,such as garlic polysaccharide,reducing sugar,crude protein,polyphenol,alliin,and garlic enzyme were measured. Results indicated that the garlic polysaccharide content had an obviously declined trend,reducing sugar and crude protein was obviously increased,these three ingredients content in S17 samples was respectively 3.01%,47.84% and15.43%.Polyphenol kept generally on rising,the content of total polyphenol in S17 was 3.37 times as that in normal garlic,effect of discard water content could be as much as 7.94 times.Concentration of garlic enzyme was on the decline trend,which completely deactivated at 93℃.Alliin increased after the first decline,the lowest point was 0.32 times as that of normal garlic and the highest point was 0.41 times as that of normal garlic.Based on the regularity of component analysis of data,S10 samples were identified as a key inflection point indicating change.According to the taste and sensory evaluation,7d was considered as the key parameter when adjust the process in the fermentation.