| 1965–66 Cuban National Series | |
| League: | Cuban National Series |
| Sport: | Baseball |
| No Of Games: | 65 |
| No Of Teams: | 6 |
| Season: | Regular season |
| Season Champ Name: | Champion |
| Season Champs: | Industriales (40–25) |
| Seasonslistnames: | SNB |
| Prevseason Link: | 1964–65 Cuban National Series |
| Prevseason Year: | 1964–65 |
| Nextseason Link: | 1966–67 Cuban National Series |
| Nextseason Year: | 1966–67 |
The fifth season of the Cuban National Series saw expansion both in the number of teams and the number of games played. Two new teams, Henequeneros and Centrales, were formed, and the schedule was nearly doubled, from 39 games per team to 65.
Industriales, after two years of dominating the standings, came back to the pack, as Orientales and the new Henequeneros squad were within three games of winning the title. However, Industriales were able to win their fourth straight series.
| Team | W | L | Pct. | GB | |
|---|---|---|---|---|---|
| 40 | 25 | .615 | - | ||
| Orientales | 38 | 27 | .585 | 2 | |
| Henequeneros | 37 | 28 | .569 | 3 | |
| Occidentales | 29 | 35 | .453 | 10½ | |
| Granjeros | 26 | 38 | .406 | 13½ | |
| Centrales | 23 | 40 | .365 | 16 |