Abstract: This article’s aim was to adopt PCR -DGGE method to study the effect of feeding Lactobacillus plantarum to antibiotic intestinal flora in mice on the gut microflora. Female KM mice were continuously fed with cefdinir solution for five days to cause antibiotic-associated intestinal flora in them, and then treated by oral gavage of Lactobacillus plantarum (10 9 CFU/mL) for another 5 days. Feces were abstracted and 16S rDNA-based PCR-DGGE method was used to analyze the influence of Lactobacillus plantarum adjustment process on the microbial community structure and diversity. The main preponderant strips were rubber cutting cloned and sequenced. PCR-DGGE profiles showed that with the extension of the Lactobacillus plantarum feeding time, the richness of the mouse intestinal flora presented a gradual increase in the successionprocess. The richness index (18) and diversity index (2.75) of the intestinal flora after the mice were gavaged using Lactobacillus plantarum for fourth day were the same as the normal ones. DGGE profiles, sequencing results showed that plant lactobacillus control mice intestinal dysbacteriosis mainly manifested in two aspects:selective increase beneficial bacteria such as Bacteroides stercoris, Bacteroides uniformis strain of quantity. Inhibition of pathogenic bacteria such as Clostridium clostridioforme, Pseudomonas stutzeri growth, etc. Results showed that the Lactobacillus plantarum had adjustment effect on intestinal flora disorder caused by cefdinir. Establishment of PCR-DGGE method analysis methods were in order to monitor the dynamic changes of intestinal flora, and to lay the foundation for further study of probiotics on the mechanism of action of the intestinal flora.