A 39-year-old man with human immunodeficiency virus (HIV) infection that was being treated with antiretroviral therapy presented to the dermatology clinic with a 1-year history of recurrent, painful penile ulcers. Approximately once per month, erosions would appear on his penile shaft, ulcerate, heal without specific treatment, and then recur. On physical examination, there were two exophytic plaques with central ulceration and raised borders. There were also hypopigmented patches at the sites of healed lesions. Laboratory testing showed a CD4 cell count of 494 per cubic millimeter (reference range, 414 to 1123) and an HIV viral load of 450 copies per milliliter (reference range, <20). Biopsies of the lesions revealed epidermal necrosis, pseudoepitheliomatous epidermal hyperplasia, and a dense infiltrate of inflammatory cells in the dermis and subcutaneous tissue. A next-generation sequencing assay to detect sexually transmitted infection (STI) identified herpes simplex virus (HSV) type 2. Other microbiologic testing was negative. A diagnosis of herpes vegetans was made. Herpes vegetans — also known as hypertrophic herpes simplex — is an uncommon manifestation of HSV infection seen in persons with immunocompromise. It manifests as verrucous, proliferative, or ulcerative lesions, often with a chronic, persistent course. Treatment with oral valacyclovir was given. Screening for other STIs was negative. At a 2-week follow-up, the lesions had abated.