Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) characterized by chronic inflammation affecting the colonic mucosa, that can extend to the whole large bowel. The severity of mucosal lesions directly reflects the disease activity and severity and may be prognostic for an aggressive behavior of the pathology. Remission, is usually defined as resolution of symptoms. Recently, mucosal healing (MH) has emerged as an important end point of any short-term medical therapy for IBD. It may predict long-term remission and may impact on the natural history of the disease in Crohn's disease (CD), while data in UC patients are still limited. This review of the literature is focused on the recent evidence on the impact of medications on MH in UC and on the impact of MH on the natural course of UC.