The 1940 Montana gubernatorial election took place on November 5, 1940. Incumbent Governor of Montana Roy E. Ayers, who was first elected governor in 1936, ran for re-election. He narrowly won the Democratic primary by just over a thousand votes to win renomination, and advanced to the general election, where he was opposed by Sam C. Ford, a former Associate Justice of the Montana Supreme Court and the Republican nominee. Ultimately, in spite of the fact that then-President Franklin D. Roosevelt comfortably won the state in that year's presidential election, Ford narrowly defeated Ayers to win his first of two terms as governor.
- Roy E. Ayers, incumbent Governor of Montana
- Arthur F. Lamey, former Chairman of the Montana Democratic Party, former Hill County Attorney
- A. E. Kathan
|Democratic||Roy E. Ayers (incumbent)||40,268||38.23|
|Democratic||Arthur F. Lamey||39,010||37.04|
|Democratic||A. E. Kathan||26,041||24.73|
- Sam C. Ford, former Associate Justice of the Montana Supreme Court
- Charles A. Hauswirth, Mayor of Butte
- Julius J. Wuerthner, former Mayor of Great Falls
- T. S. Stockdahl
- Martin P. Moe, former Secretary of the Montana Education Association
- John H. Leuthold
|Republican||Sam C. Ford||16,335||32.90|
|Republican||Charles A. Hauswirth||14,397||29.00|
|Republican||Julius J. Wuerthner||8,685||17.49|
|Republican||T. S. Stockdahl||5,439||10.95|
|Republican||Martin P. Moe||3,994||8.04|
|Republican||John H. Leuthold||802||1.62|
|Republican||Sam C. Ford||124,435||50.67%||+2.55%|
|Democratic||Roy E. Ayers (incumbent)||119,453||48.64%||-2.31%|
|Republican gain from Democratic||Swing|
- "Report of the Official Canvass of the Vote Cast at the Primary Election Held in the State of Montana, July 16, 1940" (PDF). Montana Secretary of State. Archived from the original (PDF) on 2013-12-28. Retrieved July 5, 2014.
- "Official Montana General Election Returns, November 5, 1940" (PDF). Montana Secretary of State. Archived from the original (PDF) on May 28, 2013. Retrieved July 6, 2014.