The 1940 Arizona gubernatorial election took place on November 5, 1940. Incumbent Governor Robert Taylor Jones ran for reelection but was defeated in the Democratic primary by former Secretary of State Sidney Preston Osborn, whom Jones had previously defeated in 1938.
Sidney Preston Osborn defeated Jerrie W. Lee in the general election, and was sworn into his first term as Governor on January 6, 1941, becoming Arizona's seventh Governor.
The Democratic primary took place on September 10, 1940. Incumbent Governor Robert Taylor Jones ran for reelection, but he was defeated by former Secretary of State Sidney Preston Osborn. Osborn previously ran against Jones in 1938, but was defeated due to the race being a three-way with Secretary of State James H. Kerby. C. M. Menderson, Ernest Carleton, George E. Shields, and Howard Sprouse also ran but presented only token opposition.