Fathi Bashagha’s announcement follows the more high-profile candidacies of Aguila Saleh, Khalifa Haftar and Saif al Islam Gaddafi in the race for the country’s highest office after years of civil war.
Libya's former interior minister Fathi Bashagha has registered to run in the presidential election in December.
He joined a field of prospective candidates on Thursday that includes late ousted dictator Muammar Gaddafi's son Saif al Islam Gaddafi, warlord Khalifa Haftar, and the eastern-based parliament, House of Representatives speaker Aguila Saleh.
Bashagha was the influential interior minister in the internationally recognised Government of National Accord (GNA) who was replaced in March by a new unity government.
A UN-backed peace process calls for presidential and parliamentary elections on December 24 but there has been no widespread agreement on the legal basis for the vote.
Disputes between rival factions and political entities have focused on questions over who should be allowed to run, the eventual role of the directly elected president and the voting schedule.
Analysts say the arguments surrounding the elections threaten to derail the peace process, whether the vote goes ahead or not.
Libya has been wracked by chaos since a NATO-backed uprising toppled Gaddafi in 2011, who was later killed.
READ MORE: Q&A: Why Libya’s elections must be delayed