Interstate 44 (I-44) is an Interstate Highway that runs diagonally through the U.S. state of Oklahoma, spanning from the Texas state line near Wichita Falls, Texas, to the Missouri border near Joplin, Missouri. It connects three of Oklahoma's largest cities: Oklahoma City, Tulsa, and Lawton. Most of I-44 in Oklahoma is a toll road. In southwestern Oklahoma, I-44 is the H. E. Bailey Turnpike and follows a diagonally northeast–southwest direction. From Oklahoma City to Tulsa, I-44 follows the Turner Turnpike. After leaving Tulsa, I-44 follows the Will Rogers Turnpike to the Missouri state line west of Joplin, Missouri. In the Lawton, Oklahoma City, and Tulsa metropolitan areas, I-44 is toll-free. In Oklahoma City, I-44 is also known as the Will Rogers Expressway.

I-44 is paralleled by former U.S. Highway 66 (US-66, now mostly State Highway 66, or SH-66) from Oklahoma City to the Missouri state line.

I-44 crosses the Red River near Burkburnett, Texas. It enters the state on a mostly north–south alignment. The route is toll-free until exit 5, which is the last free exit before the start of the southern section of the H. E. Bailey Turnpike. At exit 30, the tolls end, and I-44 becomes a non-tolled highway again through Lawton and Fort Sill until exit 46. The northern section of the H. E. Bailey Turnpike carries I-44 north, serving Chickasha before ending at US-62 (exit 107) in Newcastle.

From Newcastle, I-44 enters a northeast–southwest alignment and heads north through rural parts of Oklahoma City before it briefly enters a wrong-way concurrency with I-240. It then indirectly serves Will Rogers World Airport by connecting to Southwest 59th Street (which becomes Southwest 54th Street before reaching the airport) and SH-152, the Airport Road freeway. I-44 meets I-40 west of downtown at an interchange sometimes referred to as the Amarillo Junction. I-44 then passes west of the state fairgrounds and continues north to provide access to Bethany and Warr Acres. It then turns more eastbound before reaching a junction with I-235, which also signifies the northern end of I-235, and US-77 also known as the Broadway Extension, which connects Downtown Oklahoma City to Edmond. It then meets and follows a stretch of I-35, which it runs concurrently with until the Turner Turnpike interchange, where it takes an easterly turn again.

I-44 then follows the Turner Turnpike to Sapulpa, where it becomes a non-tolled road after meeting SH-66. I-44 bypasses Downtown Tulsa; I-244 serves the downtown areas. After meeting the Creek Turnpike again on the east side of the city, I-44 becomes a turnpike once again, gaining the Will Rogers Turnpike designation.

The Will Rogers Turnpike section serves many northeast Oklahoma towns, including Claremore, Vinita (where it passes under the world's former largest McDonald's), and Miami. After passing Miami, I-44 crosses the state line into Missouri, about 600 feet (180 m) south of the Kansas–Missouri–Oklahoma tripoint.

I-44 was designated through Oklahoma to replace the section of US-66 running from Oklahoma City to Joplin, Missouri. I-44 covered the already-existing Turner and Will Rogers turnpikes, with a western terminus at I-35 in Oklahoma City, the current western terminus of the Turner Turnpike.

I-44 was assigned to the H. E. Bailey Turnpike in 1982, when I-44 was assigned to the western and northern legs of I-240 (then a semi-beltway around Oklahoma City) and the H. E. Bailey Turnpike as part of Oklahoma's "Diamond Jubilee" celebrations. Before I-44 was assigned to it, the freeway connector to the north end of the H. E. Bailey Turnpike was named the Will Rogers Expressway. The non-tolled section through Lawton was the Pioneer Expressway.