2004 Torneo Descentralizado
The 2004 Torneo Descentralizado was the eighty-eighth season of Peruvian football. A total of 14 teams competed in the tournament, with Alianza Lima as the defending champion. Alianza Lima won its twenty-first Primera División title after beating Sporting Cristal in the final playoff.
Changes from 2003
Structural changes
The number of teams for the 2004 season grew from 12 to 14. The relegation system was re-introduced but the system was determined by a points per match average. The qualification for the Copa Sudamericana was determined by the aggregate table instead of the Torneo Apertura playoffs. Due to a structure change in the Copa Libertadores, only two teams will qualify directly to the group stage and the best-placed non-champion will have to play in the first stage.Promotion and relegation
No teams were relegated from the 2003 season and thus the number of teams grew from 12 to 14. Segunda División champion Sport Coopsol and Copa Perú 2003 champion Universidad César Vallejo were promoted.Universidad San Martín bought the promotional place of the 2003 Segunda División winners, Sport Coopsol.
Teams
| Team | City | Stadium | Capacity | Field |
| Alianza Atlético | Sullana | Campeones del 36 | 8,000 | Grass |
| Alianza Lima | Lima | Alejandro Villanueva | 35,000 | Grass |
| Atlético Universidad | Arequipa | Virgen de Chapi | 45,000 | Grass |
| Cienciano | Cusco | Garcilaso | 42,056 | Grass |
| Coronel Bolognesi | Tacna | Jorge Basadre | 19,850 | Grass |
| Deportivo Wanka | Huancayo | Huancayo | 20,000 | Grass |
| Grau–Estudiantes | Piura | Miguel Grau | 25,000 | Grass |
| Melgar | Arequipa | Mariano Melgar | 20,000 | Grass |
| Sport Boys | Callao | Miguel Grau | 15,000 | Grass |
| Sporting Cristal | Lima | San Martín de Porres | 18,000 | Grass |
| Unión Huaral | Huaral | Julio Lores Colan | 10,000 | Grass |
| Universidad César Vallejo | Trujillo | Mansiche | 24,000 | Artificial |
| Universidad San Martín | Lima | Nacional | 18,000 | Grass |
| Universitario | Lima | Monumental | 80,093 | Grass |