| Election Name: | 1884 Boston mayoral election |
| Type: | Presidential |
| Ongoing: | no |
| Previous Election: | 1883 Boston mayoral election |
| Previous Year: | 1883 |
| Election Date: | December 9, 1884 |
| Next Election: | 1885 Boston mayoral election |
| Next Year: | 1885 |
| Image1: | Hugh O'Brien 5210004 015 028 (3x4a).jpg |
| Candidate1: | Hugh O'Brien |
| Party1: | Democratic Party (United States) |
| Popular Vote1: | 27,494 |
| Percentage1: | 53.22% |
| Candidate2: | Augustus Pearl Martin |
| Party2: | Republican Party (United States) |
| Popular Vote2: | 24,168 |
| Percentage2: | 46.78% |
| Mayor | |
| Before Election: | Augustus Pearl Martin |
| Before Party: | Republican Party (United States) |
| After Election: | Hugh O'Brien |
| After Party: | Democratic Party (United States) |
The Boston mayoral election of 1884 saw the election of Hugh O'Brien, who unseated incumbent mayor Augustus Pearl Martin.
O'Brien's victory began an era in which Irish descended men dominated the mayoralty of Boston.[1]