Rio de Janeiro Governor Ernani do Amaral Peixoto appointed Peçanha as mayor of the municipality of Bom Jardim from 1941 to 1943.

[1][2] In 1950, was elected to the federal Chamber of Deputies from Rio de Janeiro as a member of the Brazilian Labour Party (PTB).

[1][2] Celso Peçanha was elected Vice Governor of Rio de Janeiro in 1958, this time as a candidate for the Social Democratic Party (PSD).

[2] In 1978, Peçanha returned to politics when he won a seat in the Chamber of Deputies as a Brazilian Democratic Movement (MDB) candidate.

Peçanha joined the Brazilian Labour Party (PTB) in 1982, the same year that he won re-election to the Chamber of Deputies.