Workers in Parana state found the bodies of federal Deputy Jose Carlos Martinez, 55, and three others from the wreckage of the light plane, the official Agencia Brasil news agency reported.
The plane disappeared from radar Saturday while enroute from the state capital of Curitiba to Florianopolis, on Brazil's southern coast.
Martinez was head of the right-wing Brazilian Labor Party and represented Parana in the Chamber of Deputies, the lower house of Brazil's Congress.
Also on board the plane was Joao Luiz Goebel, director of the Brazilian government's radio service, Radiobras.
The cause of the crash remained under investigation.