Okinawa Prefecture - Wikipedia Okinawa Prefecture (Japanese: 沖縄県, Hepburn: Okinawa-ken; pronounced [o kʲi na wa (ꜜ keɴ)];[2] Okinawan: 沖縄県, romanized: Uchinaachin[3]) is the southernmost and westernmost prefecture of Japan [4] It consists of three main island groups—the Okinawa Islands, the Sakishima Islands, and the Daitō Islands —spread across a maritime zone approximately 1,000 kilometers east to