| Election Name: | 1884 Philadelphia mayoral election |
| Country: | Philadelphia |
| Type: | presidential |
| Ongoing: | no |
| Previous Year: | 1881 |
| Next Year: | 1887 |
| Image1: | File:William Burns Smith.jpg |
| Nominee1: | William Burns Smith |
| Party1: | Republican Party (United States) |
| Popular Vote1: | 79,552% |
| Percentage1: | 53.04% |
| Nominee2: | Samuel G. King |
| Party2: | Democratic Party (United States) |
| Popular Vote2: | 70,440 |
| Percentage2: | 46.96% |
| Mayor | |
| Before Election: | Samuel G. King |
| Before Party: | Democratic Party (United States) |
| After Election: | William Burns Smith |
| After Party: | Republican Party (United States) |
The 1884 Philadelphia mayoral election saw William Burns Smith defeat incumbent mayor Samuel G. King. This would ultimately be the last election to a three-year term as mayor, as the city subsequently extended mayoral terms to four years.