Yokosuka is a city in Kanagawa Prefecture, Japan. As of February 2024, the city has a population of 373,797, and a population density of 3,708 inhabitants per square kilometre. The total area is 100.7 km2. Yokosuka is the 11th-most populous city in the Greater Tokyo Area, and the 12th in the Kantō region. The city is home to United States Fleet Activities Yokosuka.