Emmanuel Macron made the decision "in the face of the critical humanitarian situation" in the war-torn country, his office said in a statement.
Macron met earlier with representatives of the aid groups who spelled out the humanitarian needs of a population that has endured seven years of war.
The decision comes two days after France took part in US-led air strikes on suspected chemical sites in Damascus following an alleged chemical attack in the Ghouta town of Douma.
The strikes raised fears of an escalation of the conflict in which more than 350,000 people have died, but key players on Monday appeared keen to shift the focus to diplomacy.
The projects will focus on the Idlib region where some 1.2 million displaced people live, according to UN estimates, as well as the Ghouta region near Damascus and in the northwest in areas recently liberated from the Islamic State group.
Overall, the United Nations estimates that 13 million Syrians including six million children need humanitarian aid.