| Competition: | Primeira Liga |
| Season: | 1965-66 |
| Winners: | Sporting CP 12th title |
| Matches: | 182 |
| Total Goals: | 614 |
| Prevseason: | 1964–65 |
| Nextseason: | 1966–67 |
Statistics of Portuguese Liga in the 1965/1966 season.
It was contested by 14 teams, and Sporting Clube de Portugal won the championship.