| Country: | Northern Territory |
| Type: | parliamentary |
| Ongoing: | no |
| Election Date: | 21 November 1981 |
| Party1: | Australian Labor Party (Northern Territory Branch) |
| Popular Vote1: | 822 |
| Percentage1: | 46.9% |
| Swing1: | 4.9pp |
| Candidate2: | John Robinson |
| Party2: | Country Liberal Party |
| Popular Vote2: | 703 |
| Percentage2: | 40.1% |
| Swing2: | 8.1pp |
| Candidate3: | Rosemary Harris |
| Party3: | Australian Democrats |
| Popular Vote3: | 120 |
| Percentage3: | 10.4% |
| Swing3: | 10.4pp |
| 2Blank: | TPP swing |
| 1Data1: | 54.2% |
| 2Data1: | 2.4pp |
| 1Data2: | 45.8% |
| 2Data2: | 2.4pp |
| MP | |
| Before Party: | Australian Labor Party (Northern Territory Branch) |
| After Party: | Australian Labor Party (Northern Territory Branch) |
A by-election for the seat of Millner in the Northern Territory Legislative Assembly was held on 21 November 1981. The by-election was triggered by the resignation of Labor member and Leader of the Opposition Jon Isaacs. Labor candidate and future Leader of the Opposition Terry Smith won the election against CLP candidate John Robinson.