OBJECTIVE: To establish a rat model of nonalcoholic fatty liver disease (NAFLD) using high-fat diet, and to dynamically observe the influence of the changes in gut microbiota on the development and progression of NAFLD in rats during and after modeling. METHODS: Sprague-Dawley rats were given high-fat diet to establish the model of NAFLD, and these rats were randomly divided into high-fat group, antibiotic pretreatment group, antibiotic treatment group, restricted diet group, and control group. The rats were sacrificed in different feeding periods, and 16sRNA fluorescent quantitative PCR was used to analyze the changes in ileocecal microbiota in rats. The liver pathological scores were determined, and enzymatic colorimetry was used to measure blood lipid level in serum and liver homogenate. The sample mean t-test was used for comparison between groups. RESULTS: Compared with the high-fat group, the restricted diet group showed the most significant improvements in quality of life and biochemical parameters. In the restricted diet group, the number of probiotics (Bifidobacterium and Lactobacillus) at the end of the ileum gradually increased and tended to increase over the time of intervention, and the most significant difference between this group and the high-fat group occurred at the 10th week (Bifidobacterium: 0.91±0.23 vs 0.28±0.12, P < 0.05; Lactobacillus: 0.78±0.04 vs 0.21±0.03, P < 0.05), while the number of enterococci decreased. There were no significant differences in enteric bacilli between groups (all P > 0.05). At the 10th week, the liver pathological scores in the control group, antibiotic treatment group, and restricted diet group were 1.13±1.74, 4.86±0.86, and 2.94±1.91, respectively, significantly lower than 7.09±2.03 in the high fat group (all P < 0.05). CONCLUSION: Diet structure change and antibiotic intervention can adjust gut microecology, alleviate the lesions of NAFLD, and thus provide new strategies for the prevention and treatment of NAFLD from the perspective of microecology.