| Election Name: | 1840 Ohio gubernatorial election |
| Country: | Ohio |
| Type: | Presidential |
| Ongoing: | no |
| Previous Election: | 1838 Ohio gubernatorial election |
| Previous Year: | 1838 |
| Next Election: | 1842 Ohio gubernatorial election |
| Next Year: | 1842 |
| Election Date: | October 13, 1840 |
| Nominee1: | Thomas Corwin |
| Party1: | Whig Party (United States) |
| Popular Vote1: | 145,442 |
| Percentage1: | 52.93% |
| Nominee2: | Wilson Shannon |
| Party2: | Democratic Party (United States) |
| Popular Vote2: | 129,312 |
| Percentage2: | 47.06% |
| Governor | |
| Before Election: | Wilson Shannon |
| Before Party: | Democratic Party (United States) |
| After Election: | Thomas Corwin |
| After Party: | Whig Party (United States) |
The 1840 Ohio gubernatorial election was held on October 13, 1840.
Incumbent Democratic Governor Wilson Shannon was defeated by Whig nominee, former U.S. Representative Thomas Corwin.