The 1966 Campeonato Gaúcho was the 46th season of Rio Grande do Sul's top association football league. Grêmio won their 17th title.[1][2]
Format
The championship was contested by the twelve teams in a double round-robin system, with the team with the most points winning the title and qualifying to the 1967 Taça Brasil. The last placed team was relegated to the 1967 Second Division.