| Tournament details | |
|---|---|
| Dates | February 2 – July 6 |
| Teams | 19 (from 9 associations) |
| Final positions | |
| Champions |  Independiente (4th title) |
| Runners-up |  Colo-Colo |
| Tournament statistics | |
| Matches played | 65 |
| Goals scored | 187 (2.88 per match) |
| Top scorer(s) | Carlos Caszely (9 goals) |
Copa Libertadores 1973 was won by defending champions Independiente of Argentina after defeating Colo Colo of Chile in a third decisive game. The third match which ended 2–1 in extra time was necessary after the previous two leg matches ended in draws. Their fourth consecutive title made Independiente the first team in the tournament's history to win four titles.
The Venezuelan club teams Deportivo Italia and Deportivo Galicia did not participate in the Copa Libertadores due to internal problems with the Venezuelan Football Federation.