Okinawa Prefecture (Japanese: 沖縄県, Hepburn: Okinawa-ken; pronounced [o.kʲi.na.wa(ꜜ.keɴ)]; Okinawan: 沖縄県, romanized: Uchināchin) is the southernmost and westernmost prefecture of Japan. 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 west and 400 kilometers north to south. Despite a modest land area of 2,281 km² (880 sq mi), Okinawa's territorial extent over surrounding seas makes its total area nearly half the combined size of Honshu, Shikoku, and Kyushu. Of its 160 islands, 49 are inhabited. The largest and most populous island is Okinawa Island, which hosts the capital city, Naha, as well as major urban centers such as Okinawa, Uruma, and Urasoe. The prefecture has a subtropical climate, characterized by warm temperatures and high rainfall throughout the year. People from the Nansei Islands, including Okinawa, the Sakishima Islands, and parts of Kagoshima Prefecture, are often collectively referred to as Ryukyuans. However, there are significant cultural and customary differences between individual islands and even between local communities.

Historically the center of the Ryukyu Kingdom, Okinawa long served as a maritime trading hub and cultural gateway; the kingdom participated in the Chinese tributary system—maintaining formal tribute relations with the Ming and Qing—and retained distinct statehood until it was incorporated into Japan as Okinawa Prefecture in 1879 following the Ryukyu Disposition. After the Battle of Okinawa (1945), the islands were under U.S. administration until reversion to Japan in 1972, and today host a large share of U.S. military facilities in Japan (around 70% by area of land exclusively used by U.S. forces), a continuing source of local and national debate. A small but persistent independence movement exists, reflecting Okinawa's distinct historical trajectory and identity.

Over time, Okinawa developed its own distinctive traditions, cuisine, and performing arts. Today, Okinawan music, characterized by the iconic sanshin instrument, and festivals such as Eisa have gained popularity across the country. The islands are also the birthplace of karate, later popularized on the Japanese mainland and worldwide. The prefectural economy is predominantly service-based, with tourism and related services as major drivers, while manufacturing plays a comparatively small role.

The prehistoric history of Okinawa differs significantly from that of mainland Japan. Prior to written records, it is generally divided into two periods: the Paleolithic era and the Shellmidden period (Kaizuka period). The earliest evidence of human activity in Okinawa includes the Yamashita Cave Man, dating back approximately 32,000 years, and the Minatogawa Man from around 18,000 years ago. In 2012, the world's oldest known fishhook was discovered in the Sakitari Cave site in Nanjo City, Okinawa Prefecture.

The Shellmidden Period in Okinawa roughly corresponds to the Jōmon through Heian periods of mainland Japan, with a chronological gap of about 10,000 years from the Paleolithic era.

At the Kogachibaru Shell Mound, archaeological findings include pottery styles such as Sobata and Ichiki, which originate from the Kyushu region, obsidian from Koshidake in Saga Prefecture, and jade from Itoigawa in Niigata Prefecture used for ornamental pendants. These discoveries indicate that close exchanges with Kyushu were already taking place during this time.

However, by the middle of the Shellmidden Period, Okinawan pottery began to exhibit clearly localized characteristics. Examples include the Iha and Ogido pottery styles, which are distinct to the region.

In contrast to the Shellmidden culture of Okinawa Island, which was influenced primarily by mainland Japan, the prehistoric cultures of the Miyako and Yaeyama Islands were shaped more significantly by southern cultures, including those from the Philippines.