One of the three French soldiers was seriously injured and flown to France for treatment after a suicide bomb attack on a convoy travelling between Menaka and Indelamine regions.
The attack took place on Thursday, the fifth anniversary of the start of France's military intervention against armed Islamists and Tuareg separatists in Mali.
"A vehicle approached the convoy and exploded near a VAB [armoured vehicle]," French army spokesman Patrick Steiger told the AFP news agency.
Three Malian soldiers were also injured on Thursday in an ambush in the northern town of Hombori and a policeman was abducted and a police station looted and set on fire in the north-western town of Lere, the Malian army said.
IS affiliate also claims attack that killed US soldiers
On Friday a group led by Adnan Abu Walid Sahraoui claimed responsibility for the attack that killed the French troops, as well as a number of others in Mali, Burkina Faso and Niger.
In a statement published by the private Mauritanian news agency ANI, it said it had launched the October ambush, which shocked Americans, many of who were unaware their troops were present in the region.
Sahraoui declared allegiance to IS in May 2015 but the organisation did not officially acknowledge the move until October 2016.