Brazilian legislative election, 1966

Parliamentary elections were held in Brazil on 15 November 1966. They were the first held since a military coup in 1964. In 1965, the military government of President Humberto de Alencar Castelo Branco shuttered all existing parties, and enacted a new electoral law that effectively limited the number of parties to two--the pro-government National Renewal Alliance and the opposition Brazilian Democratic Movement.

ARENA won a crushing victory, taking 277 of the 409 seats in the Chamber of Deputies and 19 of the 23 seats in the Senate. Voter turnout was 77.2% in the Chamber of Deputies election and 77.3% in the Senate election.