[Background] Alcohol affects people’s health in two ways: beneficial or harmful. Influence of alcohol on the intestinal micro-ecological system is great. [Objective] Present study was to explore the influence of alcohol intake on blood, intestinal microbiota and enzyme activities of mice. [Methods] SPF (specific pathogen free) experimental mice were randomly divided into 4 groups: control group, low dose group, medium dose group and high dose group. Mice of the control group were given sterile water to drink, other groups were given 10%, 20% and 30% (v/v) ethanol solution respectively to drink freely for 1 month. Then the mice were sacrificed, enzyme activities and microorganisms in mice intestinal contents were analyzed. Blood was collected by the eyeball method and analyzed at the same time. [Results] Compared to the control group, the amounts of lactobacillus in mice intestine of the low dose group increased significantly (P<0.05). However, the numbers of colibacillus and bacterium decreased evidently (P<0.01 or P<0.05). The amounts of lactobacillus and bifidobacteria reduced sharply (P<0.01). Compared to the low dose group and medium dose group, the activities of xylanase, protease and amylase in mice intestine of the high dose group increased obviously (P<0.01). The activities of the digestive enzymes in mice intestine of the low dose group was lower than that of the control group. Hematocrit in mice of the low dose group was lower than the control group (P<0.05). [Conclusion] Our findings suggested that high alcohol consumption induced the decrease in the number of intestinal probiotics and intestinal barrier function, but low alcohol consumption can regulate the intestinal flora and enzyme activities in mice intestine.