Thomaston is a town in Marengo County, Alabama, United States.

[7] Alabama State Route 28 (Second Avenue) passes through the town, leading west 11 miles (18 km) to Linden, the county seat, and southeast 30 miles (48 km) to Camden.

State Route 25 (Range Street) crosses SR 28 in the center of town and leads north 32 miles (51 km) to Greensboro and south 29 miles (47 km) to Thomasville.

According to the U.S. Census Bureau, Thomaston has a total area of 2.0 square miles (5.2 km2), all land.

The town drains west to Michigan Creek, which flows north to Chickasaw Bogue and is part of the Tombigbee River watershed.

The racial makeup of the town was 50.13% Black or African American, 48.56% White, and 1.31% from two or more races.

A rural health clinic is located in Thomaston and can handle small emergencies.