| State: | TN |
| Type: | Sec |
| Route: | 309 |
| Map Custom: | yes |
| Map Notes: | SR 309 highlighted in red |
| Alternate Name: | Union Grove Road |
| Length Mi: | 2.6 |
| Established: | July 1, 1983[1] |
| Direction A: | West |
| Terminus A: | near Niota |
| Direction B: | East |
| Terminus B: | in Niota |
| Counties: | McMinn |
| Previous Type: | Sec |
| Previous Route: | 308 |
| Next Type: | TN |
| Next Route: | 310 |
State Route 309 (SR 309), also known as Union Grove Road, is a 2.6adj=midNaNadj=mid east–west state highway in McMinn County, Tennessee. It serves as the primary access road from Interstate 75 (I-75, Exit 56) to the town of Niota.
SR 309 begins at an interchange with I-75 (Exit 56). It heads east past a few roadside businesses before passing through farmland as a two-lane highway. It then enters Niota and comes to an end at an intersection with U.S. Route 11 (US 11, Willson Street/SR 2) on the north side of town.