| Competition: | Campeonato Paulista – Série A1 |
| Season: | 1981 |
| Winners: | São Paulo |
| Relegated: | Noroeste |
| Continentalcup1: | Taça de Ouro |
| Continentalcup1 Qualifiers: | São Paulo Ponte Preta Inter de Limeira Santos XV de Jaú São José |
| Continentalcup2: | Taça de Prata |
| Continentalcup2 Qualifiers: | Corinthians Portuguesa Palmeiras Botafogo Juventus |
| League Topscorer: | Jorge Mendonça (Guarani) – 38 goals |
| Biggest Home Win: | Guarani 5-0 América (June 17, 1981) Ponte Preta 5-0 Santos (July 11, 1981) Ponte Preta 6-1 Taubaté (August 9, 1981) |
| Biggest Away Win: | Comercial 0-5 Guarani (June 21, 1981) Ferroviária 0-5 Taubaté (September 6, 1981) |
| Highest Scoring: | Taubaté 3-4 Marília (March 5, 1981) Taubaté 5-2 Juventus (March 8, 1981) Guarani 2-5 XV de Jaú (May 31, 1981) São José 3-4 Taubaté (July 5, 1981) Ponte Preta 6-1 Taubaté (August 9, 1981) Taubaté 5-2 Comercial (August 12, 1981) Juventus 5-2 Comercial (September 20, 1981) |
| Matches: | 537 |
| Total Goals: | 1190 |
| Prevseason: | 1980 |
| Nextseason: | 1982 |
The 1981 Campeonato Paulista da Primeira Divisão de Futebol Profissional[1] was the 80th season of São Paulo's top professional football league. São Paulo won the championship for their 13th title. Noroeste was relegated.[2]
The championship would be divided into two rounds, and each round was divided into three phases - Qualifying, in which two teams qualified into the Final phase, Regular, in which six teams qualified into the Final phase, and Final, divided into two groups of four, with the winners of each group qualifying to the Finals. The winners of each round qualified to the Championship Finals.
This stage involved twelve teams: all of the first level teams except for the eight teams that were still participating either in that year's Taça de Ouro or the Taça de Ouro. The twelve teams were divided into two groups of six, in which each team played twice against the teams of its own group. the top two teams of each group qualified to a playoff to determine the two teams that would qualify into that round's final phase.
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This stage, that happened simultaneously with the First round's Final stage, was composed of the twelve teams that had been eliminated in the First round, divided into three groups of four, in which each team played twice against the teams of its own group, with the best team in each group qualifying to the Finals, where the three teams played once against each other, the best two qualifying to the Second round's Final phase.
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Much like in the previous year,[3] the team with the fewest points would be relegated and the team with the second-fewest points would go to a playoff against the runner-up of the Second Level. only the results of the regular phases were counted. as such, Noroeste was relegated and São Bento had to dispute a playoff in neutral ground against XV de Piracicaba.[4]
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