In order to determining the optimum concentration of salt curing and providing a reference for the preparation of fermentation sausage pre-treatment, the pork was salted by four kinds of low salt concentration, then was made into sausages and fermented. The effects of pH, nitrite, TVB-N and microorganisms on the safety of sausage were analyzed and compared by national standard method under various salinity during fermentation. The results showed that lactic acid bacteria was inhibited less inhibitory at 1.5% and 2.0% salt concentration. Number of lactic acid colonies increased rapidly at the first 6 h after fermentation, and increased slowly after 6 h fermentation. When the salt concentration reached 2.5%～3.0%, the growth and reproduction of lactic acid bacteria were inhibited to a certain extent. With the salt concentration reaching 2.0%～3.0%, the colony growth and reproduction was significantly inhibited. The salt concentration had the greatest effect on the total number of colonies, and under the salt concentration range of 1.5%～3.0%, the total number of colonies after 6～9 h of fermentation decreased significantly with the increase of salt concentration. Moreover, the salt concentration also affected the pH value of fermented sausage, and the pH value decreased more rapidly under low salinity conditions. Under salt concentration of 1.5%～3.0%, the content of nitrite in sausage increased with the increase of salt concentration after 6～9 h of fermentation, and increased with the prolongation of fermentation time. In addition, TVB-N content was also affected by the concentration of salt. The probiotic fermented sausage has better nitrite and microbiological safety with 2.0%～2.5% of salt concentration.