Rolla is a city in Phelps County, Missouri, United States, midway between the larger cities of St. Louis and Springfield along I-44. The population in the 2010 United States Census was 19,559. It is the county seat of Phelps County. The Rolla Micropolitan Statistical Area consists of Phelps County.
The headquarters of the Mark Twain National Forest, the only United States National Forest in Missouri, is also located in Rolla. In addition, this is part of the Ozark Highlands American Viticultural Area, with vineyards established first by Italian immigrants to the area.