A 75-year-old male was admitted with high grade fever, general fatigue, and appetite loss. The laboratory examinations revealed leukocytosis of 31,700/mm3 (neutrophils: 88%) in the peripheral blood. Cystoscopy demonstrated multiple bladder tumor. Computed tomography revealed bilateral hydronephrosis due to bladder tumor. Bilateral nephrostomy and transurethral resection bladder tumor were performed. Histological diagnosis was squamous cell carcinoma and immunohistochemical staining of the resected tumor using antihuman granulocyte colony-stimulating factor (G-CSF) antibody showed positive staining in the cytoplasm of the tumor cells. Serum analysis revealed a high level of G-CSF 126 pg/ml (normal: less than 18.1 pg/ml). Total cystectomy and bilateral cutaneous ureterostomy were performed. He died of cancer 3.5 months after admission. This is the 48th case in Japanese literature.