Abstract： Rheumatoid arthritis(RA) is a chronic， systemic autoimmune disease with erosive， symmetric polyarthritis as its main clinical manifestation， which seriously affects the quality of life of patients. Chinese medicine believes that the basic pathogenesis of RA is that spleen deficiency is the root， and dampness toxin is the branch，and that the accumulation of spleen deficiency and dampness toxin is the important pathogenesis of RA. Under the destruction of the intestinal barrier proposed by modern medicine， the imbalance of intestinal flora and the increase of intestinal pathogens and their metabolites lead to the increase of the secretion of inflammatory factors，causing the disorder of the immune system， thus inducing RA. The above pathological mechanism is similar to the pathogenesis of RA with accumulation of spleen deficiency and dampness toxin in Chinese medicine. Taking the connection between the intestinal barrier and the physiology and pathology of spleen in Chinese medicine as the breakthrough point， the authors discussed the biological basis of the pathogenesis of RA with accumulation of spleen deficiency and dampness toxin from the aspects of intestinal mechanical barrier， immune barrier， biological barrier， intestinal flora，etc.，providing new ideas for the prevention and treatment of RA by Chinese medicine and western medicine.