Hollande told Iraq’s new president Fuad Masum that he was in Baghdad to "confirm France's support and solidarity" with the government, which "brings together all the elements of the Iraqi people".
He was also to meet parliament speaker Salim al-Juburi and Prime Minister Haidar al-Abadi, who heads a unity government approved by the Iraqi parliament on Monday.
He is accompanied by Foreign Affairs Minister Laurent Fabius and Defence Minister Jean-Yves Le Drian and will go on to the capital of the Kurdish region, Arbil, where he will deliver 15 tonnes of humanitarian aid.
In Arbil Hollande will also meet Louis Sako, the patriarch of Chaldean Christians, tens of thousands of whom have been driven out of their homes by the armed Islamists.
France has been supplying arms to Kurdish forces fighting IS, as well as flying in humanitarian aid.
The US’s Central Intelligence Agency recently estimated the number of IS fighters as between 20,000 and 31,500, higher than a previous estimate of 10,000.
Eleven years after France refused to back the US-led toppling of Saddam Hussein, Fabius on Wednesday said that it will take part in air strikes in Iraq “if necessary”.
Diplomats also say that strikes against IS in Syria are not excluded, although there is concern about their legality.
France has six Rafale fighter jets and just under 1,000 soldiers in the United Arab Emirates.
Monday’s conference of foreign affairs minsters will be jointly chaired by Hollande and al-Juburi.
It is to discuss an international military, diplomatic and humanitarian response and will also look at ways of cutting off finance to the insurgents.
Paris on Friday said that Iran may participate on condition that there is consensus on its presence.