The invention discloses a lactobacillus reuteri 22 and application thereof. The lactobacillus reuteri 22 disclosed by the invention is separated from healthy chicken flocks, is classified and named aslactobacillus reuteri, and has a preservation number of CGMCC No.17932. By detecting the performance of probiotics, the invention finds that the lactobacillus reuteri 22 has good acid resistance, cholate resistance and adhesion performance, and can inhibit growth of pathogenic bacteria. Through Animal assays, in a healthy physiological state, the lactobacillus reuteri 22 does not influence the level of inflammatory factors, but can increase the number of goblet cells and promote the increase of expression levels of related genes such as compact protein, defensin and lysozyme, can increase thelength of intestinal villi and the depth of crypt, and has the potential of maintaining intestinal mucosa barriers. Therefore, the strain is expected to be developed into probiotics for maintaining achicken intestinal mucosa barrier and guaranteeing green and healthy chicken breeding.