| Election Name: | 1931 Invercargill mayoral election |
| Country: | New Zealand |
| Type: | Presidential |
| Ongoing: | no |
| Previous Election: | 1929 Invercargill mayoral election |
| Previous Year: | 1929 |
| Next Election: | 1933 Invercargill mayoral election |
| Next Year: | 1933 |
| Election Date: | 6 May 1931 |
| Turnout: | 6,688 |
| Candidate1: | John Miller |
| Party1: | Independent politician |
| Popular Vote1: | 3,366 |
| Percentage1: | 50.32 |
| Candidate2: | John D. Campbell |
| Party2: | Independent politician |
| Popular Vote2: | 3,322 |
| Percentage2: | 49.67 |
| Mayor | |
| Before Election: | John D. Campbell |
| After Election: | John Miller |
The 1931 Invercargill mayoral election was part of the New Zealand local elections held that same year. The polling was conducted using the standard first-past-the-post electoral method.
Incumbent mayor John D. Campbell was narrowly defeated by the former mayor John Miller.
The following table gives the election results: