We report on a case of penile epithelioid sarcoma in a 29-year-old man presenting with a dorsal penile plaque that primarily was misdiagnosed as Peyronie's disease. Although the initial clinical findings of these two different entities appear similar, the consequence for the patient is severe. The only way of differentiating these disorders are histological findings. The principal microscopic characteristics of epithelioid sarcoma are the distinctive nodular arrangement, central degeneration and necrosis of the tumor cells with epithelioid appearance and eosinophilia. Immunohistochemical data (cytokeratin, epithelial membrane antigen, vimentin, CD 34, desmin) confirm the diagnosis. We conclude that in cases with slightest doubts on the diagnosis of Peyronie's disease, especially in younger men suffering from a fast-growing penile induration, a bioptic clarification of the entity should be performed to exclude a high malignant disease that can be only treated as far as it is localized by radical surgery.