We report on a patient with chronic discoid lupus erythematosus who was treated with argon-laser. The patient suffered from long-standing lesions and had been pretreated with various drugs; with no or slight improvement. After a few argon-laser applications, the treated skin lesions improved dramatically while the untreated lesional skin showed continuous disease activity. Histological and immunohistological investigations of biopsies from treated and untreated lesional skin suggest that endothelial mechanisms play a role in the generation and maintenance of discoid lesions in lupus erythematosus. This is the first reported case of successful treatment of chronic discoid skin lesions of a lupus erythematosus patient with argon-laser.