Katsuura is located on the east coast of southern Chiba Prefecture in the approximate center of the Bōsō Peninsula. It is bordered by the Pacific Ocean to the east. Cape Hachiman juts prominently into the Pacific Ocean and features lush sub-tropical vegetation. Rolling peaks of the Bōsō Hill Range give way to its rolling, sandy hills closer to the coast. Parts of the city are within the Minami Bōsō Quasi-National Park.