State Route 204 is a state route in central Ohio. It starts at SR 256 in Pickerington, and ends at US 22 near Mount Perry. At a length of 37.79 miles (60.82 km), the route is located parallel to Interstate 70 in Fairfield and Perry counties east of Columbus, the state capital.

Interstate 70 (I-70) in the US state of Ohio provides access between Indiana and West Virginia. I-70 is a major highway for traffic within, to, from, and through Ohio. The highway is a core roadway of the Columbus metropolitan area and is of additional importance in the Dayton metropolitan area.