| Competition: | Torneo Descentralizado |
| Season: | 1978 |
| Dates: | 8 July 1978 – 21 January 1979 |
| Winners: | Alianza Lima |
| Relegated: | Defensor Lima |
| Continentalcup1: | Copa Libertadores |
| Continentalcup1 Qualifiers: | Alianza Lima Universitario |
| Prevseason: | 1977 |
| Nextseason: | 1979 |
The 1978 Torneo Descentralizado, the top category of Peruvian football (soccer), was played by 16 teams. The national champion was Alianza Lima.
The season was divided into 2 stages. A Preliminary Tournament contested in two groups; this was a friendly tournament to keep teams occupied as the National Team was preparing for the 1978 World Cup Finals. The second stage was the Decentralized (league tournament); the top 2 qualified for Copa Libertadores and the last team was relegated.
| Team | City | Stadium | Capacity | Field | |
|---|---|---|---|---|---|
| 20,000 | Grass | ||||
| Alejandro Villanueva | 35,000 | Grass | |||
| 15,000 | Grass | ||||
| CampeonÃsimo | 8,000 | Grass | |||
| 24,000 | Grass | ||||
| 19,850 | Grass | ||||
| 45,750 | Grass | ||||
| 20,000 | Grass | ||||
| 45,750 | Grass | ||||
| 24,500 | Grass | ||||
| 15,000 | Grass | ||||
| 20,000 | Grass | ||||
| 15,000 | Grass | ||||
| 45,750 | Grass | ||||
| Julio Lores Colan | 10,000 | Grass | |||
| 45,750 | Grass |
Teams play each other once, either home or away. Liguilla Final was played only at the Estadio Nacional, Lima.