The Texas Department of Transportation is a Texas state government agency responsible for construction and maintenance of the state's immense state highway system and the support of the state's maritime, aviation, rail, and public transportation systems. TxDOT previously administered vehicle registration prior to the creation of the Texas Department of Motor Vehicles in November 2009.

Texas state highways are a network of highways owned and maintained by the U.S. state of Texas. The Texas Department of Transportation (TxDOT) is the state agency responsible for the day-to-day operations and maintenance of the system. Texas has the largest state highway system, followed closely by North Carolina's state highway system. In addition to the nationally numbered Interstate Highways and U.S. Highways, the highway system consists of a main network of state highways, loops, spurs, and beltways that provide local access to the other highways. The system also includes a large network of farm to market roads that connect rural areas of the state with urban areas and the rest of the state highway system. The state also owns and maintains some park and recreational roads located near and within state and national parks, as well as recreational areas. All state highways, regardless of classification, are paved roads. The Old San Antonio Road, also known as the El Camino Real, is the oldest highway in the United States, first being blazed in 1691. The length of the highways varies from US 83's 893.4 miles (1,437.8 km) inside the state borders to Spur 200 at just 0.05 miles long.