Recurrent aphthous ulcers are commonly found in the general population. They consist of minor, major, and herpetiform types. A number of factors are considered to be possible etiological factors for recurrent aphthous ulcers; however, their exact etiology remains unclear. Several systemic diseases and conditions associated with oral ulcerations and other causes of oral ulcerations must be considered during the differential diagnosis. Once a definitive diagnosis for recurrent aphthous ulceration has been made, the patient can be given palliative care for the lesions as well as advice and recommendations on nutrition, oral hygiene practices, and other factors that may be associated with his or her recurrent aphthous ulcers.