2003–04 Cuban National Series
The 43rd Cuban National Series ended with Industriales winning their record 10th title, sweeping Villa Clara in the best of seven final.
Regular season standings
Western zone
| Team | W | L | PCT. | GB |
| Sancti Spíritus | 54 | 35 | .605 | -- |
| Industriales | 51 | 38 | .563 | 3 |
| La Habana | 38 | 51 | .442 | 16 |
| Cienfuegos | 27 | 62 | .302 | 27 |
Eastern zone
| Team | W | L | PCT. | GB |
| Santiago de Cuba | 54 | 36 | .598 | -- |
| Granma | 48 | 41 | .540 | 5½ |
| Holguín | 42 | 47 | .471 | 8½ |
| Guantánamo | 34 | 55 | .384 | 19½ |