Immunosuppressed patients are at increased risk of skin cancer. A 67-year-old renal transplant recipient developed a nodular malignant melanoma after 30 years of immunosuppression with azathioprine and prednisolone. The patient died of metastatic disease 3 months after the diagnosis was made. The function of the renal graft was not affected at all. Renal transplant recipients are at high risk of developing nonmelanocytic skin tumors when on immunosuppressive therapy with cyclosporine A. Less common is the development of skin cancer during immunosuppression with azathioprine. Latest reports show the increased incidence of malignant melanoma in immunosuppressed patients. Our case illustrates the necessity of close dermatological surveillance of allograft recipients, to assure an early recognition of any malignant skin tumor and to reduce the risk of systemic metastatic disease.