In order to understand the effect of salt on intestine microorganism, enzyme activities and blood in mice, and to provide scientific basis for daily rational use of salt for human beings, the KM mice were randomly divided into five groups of A, B, C, D, E group, each group with 6 rats of half male and half female. The mice was corresponding gavaged continuously for one month according to the conversion of clinical dose of 0, 3, 6, 9, 12 g, and then the mice was collected eyeball blood to blood routine analysis as well as the contents from jejunum to ileum to microbial and enzyme activity analysis. In the aspect of intestinal microorganism, the number of Escherichia coli in mice was significantly increased after gavaged different dose of salt (P＜0.01). The number of Lactobacillus and bacteria in group B had no significantly compared with group A, but increased significantly on the number of Bifidobacterium(P＜0.01); In the aspect of intestinal enzyme activity, the protease activity of the mice was inhibited after gived salt, and the amylase activity was higher by giving higher salt. The activity of protease and amylase in group B was decreased compared with group A, but they were closest to that of the group A, and the xylanase and cellulase activity of group B improved significantly compared with group A (P＜0.01 or P＜0.05); In the aspect of blood routine, mean platelet volume, platelet volume distribution width of group B, C, D or E decreased significantly compared with group A. The platelet count, red blood cell hemoglobin concentration, leukocyte count and lymphocyte count in the group B were the highest. The different dose of salt has different effect on intestine microbes, enzyme activities and blood in mice, and the effect of the dose according to adult 3 g was better than the rest of the dose.