| Election Name: | 1842 Illinois gubernatorial election |
| Country: | Illinois |
| Type: | presidential |
| Ongoing: | Yes |
| Previous Election: | 1838 Illinois gubernatorial election |
| Previous Year: | 1838 |
| Next Election: | 1846 Illinois gubernatorial election |
| Next Year: | 1846 |
| Election Date: | August 1, 1842 |
| Image1: | Thomas Ford (cropped).png |
| Nominee1: | Thomas Ford (replacing Adam W. Snyder †) |
| Party1: | Democratic Party (United States) |
| Popular Vote1: | 46,452 |
| Percentage1: | 53.52% |
| Nominee2: | Joseph Duncan |
| Party2: | Whig Party (United States) |
| Popular Vote2: | 39,429 |
| Percentage2: | 45.43% |
| Map Size: | 150px |
| Governor | |
| Before Election: | Thomas Carlin |
| Before Party: | Democratic Party (United States) |
| After Election: | Thomas Ford |
| After Party: | Democratic Party (United States) |
The 1842 Illinois gubernatorial election was the seventh quadrennial election for this office. Democrat Thomas Ford, who replaced the original Democratic nominee Adam W. Snyder following his death, defeated former Whig governor Joseph Duncan, who was running for a nonconsecutive second term.[1]