Abstract: With the aging of the global population, about 80% of the elderly suffer from at least one chronic disease. Studies have found that the body′s gut microbes play an indispensable role in the occurrence and development of chronic diseases. Oxidized tea polyphenols（OTP） are compounds that have multiple biological activities after being oxidized by polyphenol oxidase, such as anti-oxidation, scavenging free radicals and anti-virus. To probe the contact of OTP on the gut microbes of the elderly, this research selected 25 month-old Sprague-Dawley（SD） rats as the aging model and randomly divided them into a control group（CK）（n=4）, OTP control group（COTP）（n=4）, high-fat group（HFD）（n=4） and OTP high-fat Group（HFOTP）（n=3）. Feces of the aged rats were collected eight weeks later for metagenomic analysis. The analysis found that the HFOTP group significantly changed the environment of the intestinal flora of old rats at the phylum and genus level, and the ratio of Firmicutes to Bacteroides was also remarkably reduced; Through principal component, multi-dimensional scale and species abundance clustering analysis showed that OTP significantly changed the structure of intestinal flora of high-fat diet elderly rats; the estimate of differences between groups showed that Ruminococcus＿R.flavefaciens and Firmicutes＿CAG:110 played a predominant role in improving the intestinal homeostasis of high-fat diet Effect; According to the evaluation of the KEGG database, it is found that the number of genes enriched in the metabolism-related pathways of the HFOTP group is the largest, mainly concentrated in carbohydrate metabolism, amino acid metabolism, nucleic acid metabolism and glycogen synthesis metabolism; The functional abundance results of KEGG differential function pathways show that the putative ABC transport system ATP-binding protein and chromosome partitioning protein in HFOTP were significantly reduced. The above results indicate that OTP may improve the health status of old rats on a high-fat diet by changing the intestinal microbial community structure.