A 49-year-old man with human immunodeficiency virus (HIV) infection presented to the HIV clinic with a several-week history of multiple slow-growing, violaceous, ulcerated lesions on the glans penis and external urethral meatus. He was sexually active with male partners and had not taken prescribed antiretroviral therapy for 2 years. Laboratory studies showed a CD4 cell count of 48 per cubic millimeter (normal range, 500 to 1200) and an HIV viral load of 395,913 copies per milliliter. Tests for herpes simplex virus infection, syphilis, gonorrhea, and chlamydia were negative. An incisional biopsy was performed, and a diagnosis of Kaposi’s sarcoma was made. Computed tomography of the chest, abdomen, and pelvis did not show any extracutaneous involvement. Kaposi’s sarcoma is a cancer caused by human herpesvirus 8, typically in the context of immunodeficiency. With treatment, the patient’s penile lesions resolved completely.