Summary The oral manifesations seen in a patient with lupus erythematosus have been described. Although the disease is seen infrequently, the dentist observing a xerostomic patient, with or without oral or dermal lesions, should be aware of the possibility of systemic disease as an etiologic factor. A review of the literature shows a low percentage of mouth lesions associated with this disease. The oral lesion is, therefore, an unreliable diagnostic sign. Xerostomia associated with lupus is practically ignored in the pathology texts but would seem a reliable sign because of the characteristic dysfunction of the salivary glands and ducts and the concurrent mouth-breathing associated with lupus erythematosus. In this case, salivary gland breakdown and duct occlusion produced an environment which made oral hygiene difficult and the maintenance of oral integrity an important consideration. Unusual oral changes with no obvious local cause should alert us to a possible systemic condition which is secondarily exhibiting oral symptoms. Prompt referral to a physician for further evaluation and treatment increases the chance of a favorable prognosis.