It runs 36.2 miles (58.3 km)[1] across Texas County in the Oklahoma Panhandle, from the adjoining state of Texas in the south to Kansas in the north.

State Highway 136 was designated as such to match the number of the Texas state highway to which it connects.

[2] SH-136 begins at the Texas state line about 20 miles (32 km) north of Gruver.

It runs north 13 miles (21 km) to Guymon, where it joins US-64, US-412 and SH-3 through the city.

The routes divide five miles (8 km) north of Guymon, after crossing the Beaver River, with Highway 136 running uninterrupted the remaining 18 miles (29 km) to the Kansas line.