SR 105 begins on the Obion-Dyer county line at an interchange with US 51/SR 3 (Future I-69).

It goes east to enter Dyer County and Trimble to have an intersection with SR 211.

It then passes through town to have an intersection with SR 89 before turning south, where the highway then leaves Trimble and winds its way southeast through farmland to cross into Gibson County.

The highway then leaves Bradford and winds its way southeast to cross into Carroll County.

The highway then leaves Trezevant and continues southeast to enter McLemoresville and comes to an end at an intersection with US 70A/SR 77.