| Election Name: | 1851 Pennsylvania gubernatorial election |
| Country: | Pennsylvania |
| Type: | presidential |
| Ongoing: | no |
| Previous Election: | 1848 Pennsylvania gubernatorial election |
| Previous Year: | 1848 |
| Next Election: | 1854 Pennsylvania gubernatorial election |
| Next Year: | 1854 |
| Party1: | Democratic Party (United States) |
| Nominee1: | William Bigler |
| Popular Vote1: | 186,489 |
| Percentage1: | 50.9% |
| Nominee2: | William F. Johnston |
| Party2: | Whig Party (United States) |
| Popular Vote2: | 178,034 |
| Percentage2: | 48.6% |
| Map Size: | 250px |
| Governor | |
| Before Election: | William F. Johnston |
| Before Party: | Whig Party (United States) |
| After Election: | William Bigler |
| After Party: | Democratic Party (United States) |
The 1851 Pennsylvania gubernatorial election occurred on October 14, 1851. Incumbent governor William F. Johnston, a Whig, was a candidate for re-election but was narrowly defeated by Democratic candidate William Bigler.