Isolated metastatic tumors of the urinary bladder are extremely rare. We report three cases of isolated bladder metastasis from stomach cancer, which were proved at transurethral biopsy or total cystectomy. The lesions appeared as focal or diffuse thickening of the bladder wall on computed tomography. No other metastatic lesion was detected on imaging studies, which made the diagnosis of bladder metastasis difficult. The possibility of metastatic bladder tumor should be considered when the bladder wall is thickened focally or diffusely in a patient treated with stomach cancer.