It travels within portions of Clayton, Fulton, and Cobb counties and connects the southern suburbs of Atlanta with the town of Mableton, west of the city.

The highway intersects SR 314 (West Fayetteville Road) and then runs along the southwestern part of the Hartsfield–Jackson Atlanta International Airport.

At SR 6 (Camp Creek Parkway), they run concurrently to the east.

They pass through the Oakland City neighborhood before SR 139 departs to the west on Ralph David Abernathy Boulevard.

It passes through rural areas until it meets its northern terminus, an intersection with US 78/US 278/SR 8 (Veterans Memorial Highway SW), in Mableton.