U.S. Route 80 is a U.S. highway that begins in the state of Texas in Dallas at an interchange with I-30. US 80 runs in an east-west direction for most of its length from Dallas to Louisiana.

The current route of US 80 in Texas is significantly shorter than it was when the highway was completed in 1931. The highway used to run from the New Mexico state line, near El Paso, to the Louisiana state line. Much of the highway was bypassed/replaced by the Interstate Highway System. US 80 has been replaced by I-10 from New Mexico to I-20, southwest of Pecos. The rest of the highway has been replaced by I-20 from here to the highway's current start in Dallas. The old highway has since been replaced by local roads and state highways (see below).

The current highway begins as a freeway at I-30 in Dallas, almost in Mesquite. This freeway runs from Dallas to Spur 557 between Forney and Terrell. This freeway was originally part of I-20 and is built to Interstate standards. The freeway passes through the suburbs of Mesquite, Sunnyvale (the only freeway to directly serve the town), and Forney.

In Terrell, US 80 serves as the major east-west highway in the town, passing through the town square. US 80 leaves Terrell serving smaller communities, such as Elmo. US 80 intersects SH 19 east of Edgewood. The highway runs in mostly a straight line from Terrell to Mineola, where it intersects US 69 about 30 miles north of Tyler.

US 80 leaves Mineola running in a slight southeast direction towards Longview. From here, the highway turns in a slight northeast direction traveling into Marshall. The highway soon overlaps I-20, leaving the interstate to serve the community of Waskom. The two highways cross into Louisiana, parallel with each other traveling to Shreveport.