The incident occurred after the peacekeepers’ vehicle hit an improvised explosive device, the UN said late on Wednesday.
Northern Mali is home to a separatist movement. Islamist militants also have staged a series of attacks in the past year both in Mali and in neighboring countries such as Burkina Faso.
The UN Multidimensional Integrated Stabilization Mission in Mali (MINUSMA) was established in April 2013.
Twelve peacekeepers have been killed since the start of the year in the Kidal region, where Wednesday’s assault took place.