Primary small cell carcinoma of the urinary bladder is a highly aggressive disease and accounts for less than 0.5% of all primary bladder tumors. Quite often, clinical presentation is related to local and/or systemic involvement of the disease. Histogenesis is still unknown, but investigators consider the tumor originating from a multipotent undifferentiated stem cell of the bladder urothelium. Hematuria is the first and most frequent symptom that patients complain at the clinical presentation of the disease. The primary local tumor is treated by radical surgery or radiation therapy, while systemic involvement requires polychemotherapy according to the M-VAC protocol. Prognosis is worse and related to the pathological stage of the disease and to chemotherapy reply. Herein we report on 3 cases of primary small cell carcinoma of the urinary biadder. We also review and update the literature concerning this topic.