West Java (Indonesian: Jawa Barat) is a province of Indonesia on the western part of the island of Java, with its provincial capital in Bandung. West Java is bordered by the province of Banten and the country's capital region of Jakarta to the west, the Java Sea to the north, the province of Central Java to the east and the Indian Ocean to the south. With Banten, this province is the native homeland of the Sundanese people, the second-largest ethnic group in Indonesia.

West Java was one of the first eight provinces of Indonesia formed following the country's independence proclamation and was later legally re-established on 14 July 1950. In 1966, the city of Jakarta was split off from West Java as a 'special capital region' (Daerah Khusus Ibukota), with a status equivalent to that of a province, while in 2000 the western parts of the province were in turn split away to form a separate Banten province.

Even following these split-offs, West Java is the most populous province of Indonesia with a population of 48,274,160 as of the 2020 Census, which grew to 49,405,808 at mid 2022 according to the official estimates. The province's largest cities, Bekasi (a satellite city within the Jakarta metropolitan area) and Bandung, are the third and fourth most populous cities in Indonesia respectively. Bandung is also one of the most densely populated cities proper in the world.