Interstate 35 (I-35), in the US State of Oklahoma, runs from the Red River at the Texas border to the Kansas state line near Braman for a length of 236 miles (380 km). I-35 has one auxiliary route in the state, I-235, in the inner city of Oklahoma City. A second auxiliary route, I-335, is planned as the designation for the Kickapoo Turnpike, although it will not meet I-35 until the southern extension of the turnpike to a junction with I-35 in Purcell is built. Excluding the Panhandle, I-35 forms the informal bisector for central Oklahoma, and along with US 81/US 283 in western Oklahoma and US 69/US 75 in the eastern portion, it provides one of the main north-south corridors through the state.

Interstate 235 (I-235) in Oklahoma is also known as the Centennial Expressway or the I-235 Central Expressway. The spur route of I-35 is a 5.4-mile-long (8.7 km) north–south alignment in central and north-central Oklahoma City. It connects northbound to U.S. Highway 77 (US-77) to suburban Edmond and southbound at I-44 on to I-35 and the I-40 Crosstown Expressway near downtown Oklahoma City. US-77 is concurrent with I-235 for the entire route. South of its junction with I-40, I-235 becomes I-35.