Ohio State Route 378

State Route 378
Route information
Maintained by ODOT
Length9.46 mi (15.22 km)
Existed1935–present
Major junctions
South end SR 243 in Union Township
North end SR 141 in Aid Township
Location
CountryUnited States
StateOhio
CountiesLawrence
Highway system
  • Ohio State Highway System
SR 377 SR 379

State Route 378 (SR 378) is a northsouth state highway in the south-central portion of Ohio. SR 378's southern terminus is at SR 243 about 5 miles (8.0 km) south of the unincorporated community of Willow Wood. Its northern terminus is at SR 141 nearly 4 miles (6.4 km) northwest of Willow Wood.

Created in the mid-1930s, and existing entirely in Lawrence County, SR 378 parallels Symmes Creek for its entire length. A part of the northern segment of the state highway runs through a small section of Wayne National Forest.