| State: | OH |
| Type: | SR |
| Route: | 677 |
| Map: | OH 677 map.svg |
| Maint: | ODOT |
| Length Mi: | 4.78 |
| Length Round: | 2 |
| Length Ref: | [1] |
| Established: | 1937 |
| Direction A: | South |
| Terminus A: | near McArthur |
| Direction B: | North |
| Terminus B: | in Zaleski |
| Counties: | Vinton |
| Previous Type: | SR |
| Previous Route: | 676 |
| Next Type: | SR |
| Next Route: | 678 |
State Route 677 (SR 677) is a nearly 5adj=midNaNadj=mid north - south running state route existing entirely in Vinton County, Ohio. Its southern terminus is at US 50, slightly to the east of McArthur in Elk Township, and its northern terminus is at SR 278 in Zaleski. The route passes through rural east-central Vinton County while connecting the two towns. Locally, the route is known as Powder Plant Road, as an Austin Powder Company explosives plant lies along the route.
All of SR 677 is situated within Vinton County. The highway is not included as a part of the National Highway System.[2]
SR 677 first appeared in 1937 along the path between US 50 and SR 278 that it maintains to this day. The highway has not experienced any major changes since its first appearance.[3] [4]