Elected deputy in 1863, he joined the opposition to the Second Empire regime. From 31 January to 4 February 1871, Pelletan exercised the duties of public education minister, but he departed for Bordeaux on 6 February. Elected to the National Assembly in February 1871, he approved the politics of Thiers and became vice-president of the Senate in 1879.
In 1884, he was elected senator for life.
He was the father of Charles Camille Pelletan (1846–1915), French politician and journalist.