Small cell carcinoma of the urinary bladder is an extremely rare tumor accounting for less than 1% of all cancers arising from the bladder. Since the tumor is very rare, pathogenesis is uncertain. The tumor shares similar histological features with the small cell carcinoma originating at the other sites in body. However, its similar clinical features like the conventional transitional cell carcinoma of the bladder, tendency to present at a advanced stage and low immunoreactivity to the conventional neuroendocrine markers makes the early diagnosis challenging and simultaneously crucial for the patient's survival. The unknown etiology and natural history of small cell carcinoma of the urinary bladder represent a challenge both to the pathologist and urologists for its diagnosis and treatment, respectively. Considering the very few numbers of case reports available in the literature and lack of the definitive data predicting the therapeutic response to various modalities, we, herein, describe a case of small cell carcinoma originating in the urinary bladder in a female patient who was treated at our institute.