SR 155 begins at an intersection with US 19/US 41/SR 3/SR 7 south of Griffin, in Spalding County.

They cross a Norfolk Southern Railway until SR 155 departs to the east.

[1] SR 155 continues to the north-northwest to Snapfinger and turns west on Flat Shoals Parkway.

The highway heads through Panthersville and meets I-20 on the northeast edge of it.

SR 155 curves to the northeast to meet its northern terminus, an intersection with US 23/SR 13, south of Chamblee.