French President François Hollande paid tribute to Julien Barbé, a soldier from the western town of Angers who was killed overnight by enemy fire.
Barbé's unit was ambushed as they were assisting the crew of a lightly armoured vehicle hit by an improvised explosive device, or IED. Two soldiers were injured in the blast.
The ambush took place about 200 kilometres southwest of Gao, near the Burkinabe border.
Barbé's death marks the 19th French soldier killed in Mali since a French-led military intervention was launched in 2013 to drive back Islamist militants, including al Qaeda-linked groups, which had seized much of the country's north.