Small cell carcinoma of the urinary bladder (SCBC) is a type of rare malignant tumor of the urinary tract. As it does not have specific symptoms and its epidemiological features are similar to transitional cell carcinoma of the bladder, it is often misdiagnosed. SCBC is highly aggressive, metastasizes very early and has a poor prognosis, and consequently, it has become a focus for urological surgeons and oncologists. An 82-year-old male visited the Department of Urinary Surgery, in the Affiliated Hospital of Guangdong Medical College (Zhanjiang, China), due to gross hematuria that had persisted for one week. Abdominal computed tomography showed a neoplasm of ~6×6×7 cm on the anterior wall of the bladder. The initial diagnosis was of uroepithelial cell carcinoma of the bladder and surgery was performed to remove the tumor. However, the subsequent pathological examination suggested that the tumor was an SCBC. Small cell carcinoma is a highly malignant disease, with a high mortality rate, and it rarely occurs in the bladder. Upon review of a large number of studies, SCBC was not found to present with specific symptoms, making the early diagnosis of the disease difficult, however, commonly occurring symptoms included dysuria, painless gross hematuria and urinary tract obstruction.