Diu district /ˈdiːuː/ (Indo-Portuguese; Distrito de Dio) is one of the three districts of the union territory of Dadra and Nagar Haveli and Daman and Diu of India. The district is made up of Diu Island and two small enclaves on the Indian mainland. The district headquarters are at Diu Town. It is the ninth least populous district in the country (out of 640).