Abstract Background Primary malignant melanoma (PMM) of the bladder represents a very rare clinic-pathologic entity. Given the rarity of the disease, the best treatment option is not well recognized. Case presentation We describe a case of neoplasm of the bladder in a 74 years-old Caucasian man presenting with massive hematuria. Based on clinical, instrumental and histological findings a diagnosis of PMM was made. The patient underwent trans urethral resection of bladder tumor plus intravesical Bacillus Calmette–Guérin. Conclusions To make a correct diagnosis, clinical history, endoscopic evaluation, histopathological examination and immunohistochemistry, are necessary. Multidisciplinary evaluation is required to discriminate primary from metastatic malignant melanoma.