Ava is the only incorporated city in Douglas County, Missouri, United States. The population was 2,993 at the 2010 census. Ava is the county seat of Douglas County. The city was founded in 1871. It was renamed Ava in 1881, the town's original name having been "Militia Springs."
Ava is located in the southern portion of the Missouri Ozarks within the southern escarpment of the Salem Plateau. The lakes of the White River basin of northern Arkansas and southern Missouri lie to the south. The town is at the intersection of Missouri highways 5, 14 and 76. Mansfield is 13 miles to the north and Gainesville is approximately 30 miles south. Elevation of the town varies from 1,150 to 1,400 feet (350 to 430 m).
According to the United States Census Bureau, the city has a total area of 3.30 square miles (8.55 km2), all land.
Ava is home to co-owned radio stations KKOZ 1430 AM and KKOZ 92.1 FM.
The area was settled during the 1830s and Douglas County was incorporated in 1857, with Vera Cruz as county seat. In 1864, the town of Militia Springs was founded and became the new county seat in 1870.