Recurrent aphthous stomatitis (RAS) is one of the common clinical oral diseases that produces painful ulcerations in the oral cavity .It is also called canker sore or mouth ulcer. Although , the clinical features and characteristics of this disease are easily defined , the etiology and the pathophysiology remain unclear. So as a result, the available treatments still remaining unsatisfactory with the ability to reduce the severity , healing time and the frequency of recurrence of ulceration with no permanent and definitive treatment. The healing time ranges usually from seven to fourteen days. This review discusses the different treatment modalities and updates that are available to the moment and according to the severity of the ulceration, the clinician can decide to go with topical , physical or systemic treatments which give the clinician broad and detailed picture to deal with RAS in an appropriate way .