| Election Name: | 1865 Connecticut gubernatorial election |
| Country: | Connecticut |
| Type: | Presidential |
| Ongoing: | no |
| Previous Election: | 1864 Connecticut gubernatorial election |
| Previous Year: | 1864 |
| Next Election: | 1866 Connecticut gubernatorial election |
| Next Year: | 1866 |
| Election Date: | April 3, 1865 |
| Image1: | William Alfred Buckingham - Brady-Handy (3x4a).jpg |
| Nominee1: | William Alfred Buckingham |
| Party1: | National Union Party (United States) |
| Popular Vote1: | 42,374 |
| Percentage1: | 57.48% |
| Nominee2: | Origen S. Seymour |
| Party2: | Democratic Party (United States) |
| Popular Vote2: | 31,339 |
| Percentage2: | 42.51% |
| Map Size: | 220px |
| Governor | |
| Before Election: | William Alfred Buckingham |
| Before Party: | National Union Party (United States) |
| After Election: | William Alfred Buckingham |
| After Party: | National Union Party (United States) |
The 1865 Connecticut gubernatorial election was held on April 3, 1865, the last such election held during the American Civil War, and the last gubernatorial election in which the Republicans adopted the National Union Party name. It was a rematch of the 1864 Connecticut gubernatorial election. Incumbent governor and National Union nominee William Alfred Buckingham defeated Democratic nominee Origen S. Seymour with 57.48% of the vote. It was the eighth and last of Buckingham's consecutive victories.
Major party candidates