It is possible to observe the changes of intestinal functions, in particular absorbent, immunologic and hormonal ones, correlated to inside action of a pathogenic noxa, in the cutaneous district, thanks to clinico-dermatological manifestations. The most evident cutaneous pathologies are present in progress of inflammatory bowel diseases, however the most representative manifestations are present especially in progress of celiac disease. The importance of these associations leads to conclude that skin is the "mirror" of the small intestine, and that remembering it can be necessary for specialist and generalist in their clinical practice.