Hollande promised Nigeria support in the battle against Islamist group Boko Haram, saying France would always be ready to help combat extremism in defense of democracy.
"Your struggle is also our struggle," Hollande told delegates at a security conference in the capital Abuja ahead of Nigeria's unification centenary celebrations.
"We will always stand ready not only to provide our political support but our help every time you need it because the struggle against terrorism is also the struggle for democracy."
The pledge came just before Hollande's office announced he will visit French troops deployed in the Central African Republic on Friday and meet with the interim president of the troubled former colony .
Hollande will have talks with Catherine Samba Panza, address some of the soldiers and also meet with religious leaders during a brief stopover in the capital Bangui on his way back from Nigeria, where he is attending a summit with African leaders.
Hollande lamented some of the recent violence perpetrated by suspected by Boko Haram fighters, including the massacre earlier this week of at least 43 students in their sleep at a secondary school in the Islamists' northeast stronghold.
Despite crises in several regions, the French president maintained there was reason for optimism in Nigeria and Africa as a whole.
"Africa has a great future. It's the continent of ," he said but warned that such promise could be "impeded by insecurity".
He then vowed to double French overseas development aid to the continent within the next five years.
Hollande, guest of honour for the celebrations to mark 100 years since Nigeria's unification, was expected to hold talks on trade and investment with his Nigerian counterpart Goodluck Jonathan.
But given the deteriorating Boko Haram conflict in northern Nigeria and France's recent military interventions against militants in Mali and the Central African Republic, security was expected to feature prominently in bilateral talks.