Abstract:The effect of the fat reduction on the physicochemical and microbiological characteristics was discussed of fermented sausages.Three gradient of fat content（10%，20%，30%）was selected and the quality characteristics was tested of fermented sausage.The results showed that number of lactic acid bacteria both reached 107CFU/g at the end of process.There were significant differences in the processing of water activity in each group （p＜0.05）.The water activity of 20 percent group was significantly lower than the other two groups during process.Difference of fat content was no significant for pH value （p＞0.05）.The hardness of 20 percnt group was significantly lower thah 10 percent group after processing.TBARS was significantly increased during process（p＜0.05）.There was a significant difference between groups after processing（p＜0.05）.Comprehensive the above features，fat content of 20 percent could maintain the fermentation characteristics of mutton sausage well，a theoretical basis was provided for the development of low-fat fermented sausage.