Irritable bowel syndrome with diarrhea(IBS-D)has long duration and complex causes，the root cause of which lies in spleen，relating to heart，liver，lung and kidney.Based on the five-viscera correlation theory，the authors discussed and analyzed the etiology and pathogenesis of IBS-D；in terms of treatment，the author believed that treatment from spleen was the basic principle for treating IBS-D，and put forward further thoughts of the treatment based on the theory of liver-spleen correlation，heart-spleen correlation，spleen-kidney correlation and lung-spleen correlation.