A case of a 66-year-old Japanese woman with two synchronous urinary bladder tumors, namely verrucous carcinoma and poorly differentiated squamous cell carcinoma, is described. Both tumors were accompanied by widespread squamous metaplasia in the background and unassociated with bilharzial infection. The poorly differentiated squamous cell carcinoma, having a satellite tumor in its proximity, was large and in an advanced stage. The verrucous carcinoma was small with minimal invasion to the muscularis propria. The boundary between both tumors was well defined, suggesting colliding growth appearance. Immunoexpression of cytokeratins of verrucous carcinoma was similar to that of squamous metaplasia, and significant differences between verrucous carcinoma and poorly differentiated squamous cell carcinoma were demonstrated in their immunoexpression of cytokeratins.