Oral lesions in the context of lupus erythematosus (LE) have long been described. However, definitive agreement on about the exact nature and correct classification of these manifestations is lacking in published studies. Controversy exists on the significance of oral LE lesions regarding patient outcome. In this article, medical and dental literature on clinical and histopathological aspects of oral LE lesions are reviewed and critically discussed. A clinico-pathological correlation of oral lesions (interface mucositis-lupus mucositis) with cutaneous lesions (interface dermatitis-lupus dermatitis) is established, for those represent the mucosal counterparts of cutaneous LE. Validity about widely used but imprecise terms such as "oral ulcers", "ulcerative plaques", and others, in the context of LE, is discussed, and the uncertain relationship of these alterations to systemic disease with a worse outcome is commented. Furthermore, insights about the nature, differential diagnosis, and prognosis of oral lesions in LE patients are presented.