The present report describes a 6-year-old boy with leiomyoma of the bladder and the imaging characteristics of the lesion, including images from ultrasonography, computed tomography, and the histopathologic examination. Leiomyoma of bladder is extremely rare in children. The present case, to our knowledge, represents the second reported case of bladder leiomyoma in pediatric patients since 1966. Although preoperative imaging can be useful to assess the disease extent, the final diagnosis depends on the histopathologic examination findings. Surgical excision is the ideal option to confirm the diagnosis and to treat the disorder. The prognosis is good after complete resection.