Unlike epithelial tumors, connective tissue tumors are uncommon, representing only 3% of all bladder tumors. Leiomyoma of the bladder is the most frequent non-epithelial benign tumor of the bladder. Magnetic resonance imaging (MRI) is highly useful for diagnostic purposes and to determine the degree of extension. Only few reports of sonographic findings have been reported for leiomyoma of the bladder. The tumor usually develops within the bladder. Extravesicular formations have also been reported as well as a few intramural localizations. The characteristic feature is the absence of mucosal involvement. We analyzed the MRI findings in a case of leiomyoma of the bladder with intra and extravesicular development, inflammatory reaction of the bladder wall and uterine adherences in a woman with a past history of chronic cystitis. The role of diagnostic MRI is discussed.