Buncombe County (/ˈbʌŋkəm/ BUNK-um) is a county located in the U.S. state of North Carolina. It is classified within Western North Carolina. The 2020 census reported the population was 269,452, making it the 7th-most populous county in North Carolina. Its county seat is Asheville. Buncombe County is part of the Asheville, NC Metropolitan Statistical Area.

The area of modern day Buncombe County and its environs was originally populated by the Anigiduwagi, better known as the Cherokee people. Europeans, primarily of German, Scottish and English descent, began to live in Buncombe in the early 18th century. Some of the earliest permanent European settlers in Buncombe arrived in 1784. These European settlers frequently broke their treaties with the Cherokee, gradually dispelling them from their land in Buncombe County by force.

In 1791, Colonel William Davidson and David Vance petitioned the North Carolina House of Commons to create a new county in the western part of the state from parts of Burke and Rutherford counties. The proposal named the county as "Union County". In January 1792, the proposed new county was officially created and named after Edward Buncombe, a colonel in the American Revolutionary War . Locals referred to this area as “the state of Buncombe” due to it being so large. The original county would be split into eleven counties total. The first meeting of the county government took place in April 1792 in Colonel Davidson's barn (located on the present-day Biltmore Estate).

In December 1792 and April 1793, the county seat of Buncombe came under dispute. Commissioner John Dillard assisted with the resolution. The original documentation for the creation of Buncombe County proposed a committee of five persons to select the county seat. A dispute arose between two factions of Buncombe County residents on opposite sides of the Swannanoa River, one faction pressing for the county seat to be north of Swannanoa, which is now the center of Asheville, and the other faction demanding it to be at a place south of Swannanoa River, which later became known as the "Steam Saw Mill Place", and is now the southern part of the city of Asheville.

In December 1792, seven men met to select a courthouse location for the county. The desire was to have a courthouse closer to the community than Morganton, the closest place to record deeds at the time, due to the travel to Morganton being so laborious. The first courthouse was built at the present-day Pack Square site in Asheville.

As the population of Buncombe County increased, parts of the county were reallocated to new counties. In 1808, the western part of Buncombe County became Haywood County. In 1833, parts of Burke and Buncombe counties were combined to form Yancey County. In 1838, the southern part of what was left of Buncombe County became Henderson County. In 1851, parts of Buncombe and Yancey counties were combined to form Madison County. Finally, in 1925 the Broad River township of McDowell County was transferred to Buncombe County.

In 1820, a U.S. Congressman whose district included Buncombe County, unintentionally contributed a word to the English language. In the Sixteenth Congress, after lengthy debate on the Missouri Compromise, members of the House called for an immediate vote on that important question. Felix Walker rose to address his colleagues, insisting that his constituents expected him to make a speech "for Buncombe." It was later remarked that Walker's untimely and irrelevant oration was not just for Buncombe—it "was Buncombe." Buncombe, afterwards spelled bunkum and later shortened to bunk, became a term for empty, nonsensical talk. That, in turn, is the etymology of the verb debunk.

On June 16, 2020, Buncombe County Commissioners decided to remove several Confederate monuments including the Vance Monument which is named after North Carolina governor Zeb Vance, a slave owner who used convict labor to build the railroad to Western North Carolina.