Sol Zanetti, a 31-year-old philosophy teacher, was elected head of Option Nationale on Saturday night.
Zanetti replaces Jean-Martin Aussant, the party's founder, who recently resigned to pursue career opportunities in England.
The new leader says he will continue to make independence the focus for the hardline Option Nationale - unlike the governing Parti Quebecois.
The party finished fifth in the popular vote in last year's general election, with just under two per cent of the electorate.
Despite its low numbers, the party was seen as a threat to the PQ in terms of stealing away resources and votes.