Prostate leiomyomas are benign mesenchymal smooth muscle tumors devoid of glandular elements within the prostate or juxta-prostatic position. Leiomyomas develop in organs containing smooth muscle, including the kidney, bladder and seminal vesicle. Prostate leiomyomas are either a pure form or associated with benign prostate hyperplasia, and diagnosis is challenging, with definitive identification relying on pathology. However, imaging techniques, such as MRI, have proven to be useful diagnostic tools. We report on a 57-year-old male with lower urinary tract symptomatology who was diagnosed with a large prostate leiomyoma and underwent an open radical cystoprostatectomy and ileal conduit urinary diversion.