State Route 55 is a north–south highway in Middle Tennessee. The road begins in Lynchburg and ends in McMinnville. The current length is 53.40 mi (85.9 km).

The highway begins at an intersection with SR-50 in Lynchburg. SR-55 travels northeast as Fayetteville Highway, then it changes to Majors Blvd in downtown Lynchburg. After leaving town, the highway is called Lynchburg Highway as it goes northeast toward Tullahoma.

Upon entering Tullahoma, SR-55 crosses into Coffee County and changes names to Wilson Avenue. It starts a concurrency with SR-130 and continues eastward until both routes become concurrent with U.S. Route 41A/SR-16. These routes go southeastward through downtown as North Jackson St and later South Jackson St. SR-55 leaves the concurrency and goes northeast as East Carroll St while SR-130 goes southwest on West Carroll St. SR-55 leaves Tullahoma and becomes New Manchester Highway and then New Tullahoma Highway as it nears Manchester. It soon becomes McArthur St and continues straight through downtown Manchester, intersecting U.S. Route 41/SR-2 and Interstate 24.

It leaves Manchester and becomes McMinnville Highway. It continues northeast, into Warren County and through Morrison before becoming the southern part of th McMinnville Bypass. SR-55 continues on the bypass as H.T. Pelham Memorial Pkwy before terminating at U.S, Route 70S/SR-1 as those highways continue along the rest of the bypass around McMinnville.

A spur route called Business 55 starts in southwest McMinnville where SR-55 becomes the McMinnville Bypass. It goes northeast as South Chancery St, serving as the northern terminus for SR-108. It crosses the Barren Fork River and terminates at SR-56 in dowmtown McMinnville.