| Election Name: | 1910 Kooyong by-election |
| Ongoing: | no |
| Turnout: | 21,980 (57.3%) |
| Next Year: | 1913 |
| Next Election: | 1913 Australian federal election |
| Election Date: | 24 August 1910 |
| Previous Year: | 1910 |
| Previous Election: | 1910 Australian federal election |
| Type: | Parliamentary |
| Seats For Election: | The Kooyong seat in the House of Representatives |
| Colour3: | 888888 |
| Candidate3: | Leger Erson |
| Popular Vote3: | 1,363 |
| Percentage3: | 6.3% |
| Swing3: | 6.3 |
| Registered: | 38,394 |
| Candidate1: | Robert Best |
| Percentage1: | 55.5% |
| Percentage2: | 38.2% |
| After Party: | Liberal |
| After Election: | Robert Best |
| Before Party: | Liberal |
| Before Election: | William Knox |
| MP | |
| Swing2: | 5.5 |
| Popular Vote2: | 8,214 |
| Colour2: | 888888 |
| Party2: | Independent Liberal |
| Candidate2: | Alfred Lumsden |
| Swing1: | 0.8 |
| Popular Vote1: | 11,925 |
| Country: | Australia |
| Party1: | Liberal |
| Party3: | Independent Labour |
A by-election was held for the Australian House of Representatives seat of Kooyong on 24 August 1910. This was triggered by the resignation of Commonwealth Liberal Party (CLP) MP William Knox. It is the first by-election to be triggered by the resignation of the sitting member who did not then re-contest the seat in the by-election.
The election was won by CLP candidate Robert Best.