The Hunter Region, also commonly known as the Hunter Valley, Newcastle Region, or simply Hunter, spans the region in northern New South Wales, Australia, extending from approximately 162 km (101 mi) to 310 km (193 mi) north of Sydney. It contains the Hunter River and its tributaries with highland areas to the north and south. Situated at the northern end of the Sydney Basin bioregion, the Hunter Valley is one of the largest river valleys on the NSW coast, and is most commonly known for its wineries and coal industry.

Most of the population of the Hunter Region lives within 25 km (16 mi) of the coast, with 55% of the entire population living in the cities of Newcastle and Lake Macquarie. There are numerous other towns and villages scattered across the region in the eleven local government areas (LGAs) that make up the region. At the 2021 census the combined population of the region was 682,465, and is expected to reach over 1,000,000 people by 2031. Under Australia's wine appellation system, the Hunter Valley wine zone Australian Geographical Indication (GI) covers the entire catchment of the Hunter River and its tributaries. Within that, the Hunter region is almost as large, and includes most of the wine-producing areas, excluding the metropolitan area of Newcastle and nearby coastal areas, some national parks, and any land that was in the Mudgee Shire (at the western heights of the catchment).

The Hunter Valley wine region is one of Australia's best known wine regions, playing a pivotal role in the history of Australian wine as one of the first wine regions planted in the early 19th century. The success of the Hunter Valley wine industry has been dominated by its proximity to Sydney with its settlement and plantings in the 19th century fuelled by the trade network that linked the Hunter Valley to Sydney. The steady demand of consumers from Sydney continues to drive much of the Hunter Valley wine industry, including a factor in the economy by the tourism industry. While the Hunter Valley has been supplanted by the massive Riverina wine region as the largest producer of New South Wales wine, it still accounts for around 3% of Australia's total wine production and is one of the country's most recognisable regions.

For over 30,000 years Aboriginal Australians inhabited the land that is now known as the Hunter Valley wine region. Along with the Worimi to the north and the Awabakal to the south, the Wonnarua people developed a trading route connecting the Coquun (Hunter) Valley to the harbour now known as Sydney harbour.

The wine-making history of Hunter Valley begins with the European settlement of the Sydney and the New South Wales region of Australia in the late 18th century as a penal colony of the British Empire. The Hunter River itself was discovered, by accident, in 1797 by British Lieutenant John Shortland as he searched for escaped convicts. The region soon became a valuable source for timber and coal that fuelled the steamship trade coming out of Sydney.

Land prospector John Howe cut a path through the Australian wilderness from Sydney up to the overland area in what is now known as the (Lower) Hunter Valley proper in 1820. Today, the modern Putty Road between the cities of Windsor and Singleton follows Howe's exact path and is a major thoroughfare for wine tourists coming into the Hunter Valley from Sydney. As previous plantings in the coastal areas around Sydney succumbed to the humidity and wetness, and plantings to the west were limited by spring frost damage, northern reaches leading to the Hunter became, almost by default, the wine region of the new colony.

The expansive growth of the Hunter Valley wine industry in the mid to late 19th century arose from its monopoly position in the lucrative Sydney market. The provincial government of New South Wales had enacted regulations that placed prohibitive duties on wines from other areas such as Victoria and South Australia. Following World War I, many returning Australian veterans were given land grants in the Hunter Valley. This temporarily produced an up-tick in plantings but the global Great Depression as well as a series of devastating hail storms between 1929 and 1930 caused many growers to abandon their vineyards.

The Hunter Region is considered a transitional area between the Paleozoic rock foundation of the New England Fold Belt located to the south and the Early Permian and Middle Triassic period rock formations of the Sydney Basin to the south. Between these two geological areas is the Hunter-Mooki Thrust fault. At one time this fault was very geologically active and gave rise to the Brokenback range that feature prominently in the Hunter region. Strips of basalt found throughout the region also bear witness to the volcanic activity that has occurred in the history of this fault.