Mesaba Aviation, Inc. (operating as Mesaba Airlines) was a regional airline in the United States that operated from 1944 until it merged with Pinnacle Airlines in 2012 to form Endeavor Air. It was based in Eagan, Minnesota. From 2010 to 2012, the airline was a wholly owned subsidiary of Pinnacle Airlines Corp. with code sharing flights operated as Delta Connection for Delta Air Lines and US Airways Express for US Airways. Previously, the airline operated code sharing service as Northwest Airlink and Northwest Jetlink on behalf of Northwest Airlines which subsequently merged with Delta. Mesaba also previously operated connecting flight services in association with Republic Airlines before this air carrier was subsequently merged into Northwest. Mesaba Airlines effectively ceased operations on January 4, 2012, when all aircraft and personnel were transitioned to the Pinnacle Airlines operating certificate. Mesaba's operating certificate was surrendered on July 31, 2012.

Mesaba (from the Ojibwe language, misaabe: "Soaring Eagle") was founded in 1944 by Gordy Newstrom in the Mesabi Range city of Coleraine, Minnesota, and started operations in the same year under the name of Mesaba Aviation. It had one airplane, a Piper Cub purchased for $1,300, and it was used to shuttle employees of the Blandin Paper Mill Company from Grand Rapids, Minnesota, to Minneapolis. In 1950 Newstrom moved the company to Grand Rapids.

In 1973, the Halverson family of Duluth, Minnesota, bought Mesaba from Newstrom. Subsequently, they started regularly scheduled airline services serving Spencer, Iowa; Ely, MN; Virginia, MN; and Duluth.

The Swenson family of Thief River Falls, Minnesota, purchased Mesaba Aviation in 1977. They took the company public in 1982 as the airline began flying to destinations in Minnesota, North Dakota and South Dakota with Beechcraft Model 99 commuter turboprops.

In late 1984, Mesaba became a codeshare partner of Northwest Orient Airlines, flying regional and commuter turboprop aircraft as Northwest Airlink from small regional communities to the hub at Minneapolis-Saint Paul International Airport.

Mesaba began feeder service from Detroit Metropolitan Wayne County Airport to small airports across the east and midwest utilizing Fokker F27 and Fairchild Metroliner turboprop aircraft in 1988. Maintenance bases were established both in Detroit and Wausau, Wisconsin. The same year, Mesaba managed to add an additional 325 employees. It also expanded its network to four new routes including Cleveland, Dayton and Akron in Ohio, and Erie, Pennsylvania.

In 1991, Mesaba built two new hangar facilities, in Detroit and Wausau, Wisconsin, and added the first of 25 de Havilland Canada Dash 8 turboprop aircraft, leased from Northwest Airlines.

In 1995, Mesaba and Northwest reached an agreement to provide service with Saab 340 turboprop aircraft. By 1997, Mesaba added additional flights to several new cities including Aspen, Colorado, Bozeman, Montana and Montreal in Canada. In 1999, Forbes placed Mesaba at number 41 on their list of Top 200 Small Companies in America.