| Election Name: | 1845 Chicago mayoral election |
| Type: | presidential |
| Ongoing: | no |
| Previous Year: | 1844 |
| Next Year: | 1846 |
| Nominee1: | Augustus Garrett |
| Party1: | Democratic Party (United States) |
| Popular Vote1: | 1,072 |
| Percentage1: | 50.66% |
| Nominee2: | John H. Kinzie |
| Party2: | Whig Party (United States) |
| Popular Vote2: | 913 |
| Percentage2: | 43.15% |
| Mayor | |
| Nominee3: | Henry Smith |
| Party3: | Liberty Party (United States, 1840) |
| Popular Vote3: | 131 |
| Percentage3: | 6.19% |
| Before Election: | Augustus Garrett |
| Before Party: | Democratic Party (United States) |
| After Election: | Augustus Garrett |
| After Party: | Democratic Party (United States) |
In the Chicago mayoral election of 1845, Democratic nominee Augustus Garrett defeated Whig nominee John H. Kinzie and Liberty nominee Henry Smith by a 7.5% margin.
Garrett had previously served a term as mayor.
All candidates had previously run in Chicago mayoral elections, Garrett in 1842, 1843, and both 1844 elections; Smith in 1842, 1843 and both 1844 elections; Kinzie in 1837.