[4] The county straddles the western edge of the Cumberland Plateau, with the eastern portion of the county lying atop the Plateau, and the western portion lying on the lower Highland Rim.

The Rocky River, a tributary of the Caney Fork, forms part of the county's western border with Warren.

Big Bone Cave is located in the northwest corner of Van Buren County.

The cave is named for the discovery of the skeleton of a Giant Ground Sloth (Megalonyx jeffersoni) by saltpeter miners in 1811.

[7] As of the 2020 United States census, there were 6,168 people, 2,141 households, and 1,545 families residing in the county.

24.3% of all households were made up of individuals, while 30.6% had someone living alone who was 65 years of age or older.

This trend has reversed dramatically in recent years, with Republican candidates winning the county in each of the past four elections.