The soldiers of the UN Multidimensional Integrated Stabilization Mission in Mali (MINUSMA) were in a convoy that was attacked 30 kilometres (19 miles) west of Sevare, the UN said, according to the Times Live.
No militant group has taken responsibility for the assault.
The attack of the UN troops comes 10 days after five MINUSMA peacekeepers from Chad were killed in an ambush in the northern region of Kidal. Two days ago five Malian soldiers were killed near the town of Gao.
"I condemn in the strongest terms this despicable crime," said MINUSMA head Mahamat Saleh Annadif.
MINUSMA and French forces have been deployed in northern Mali for three years, since the local separatists joined the jihadists in order to put the region under the control of the government in Bamako.
The militants have performed a series of high profile attacks in the past year, mainly in Mali's north, but also in neighboring Burkina Faso and Ivory Coast.
A peace accord that was signed last year was to bring stability to the region, but attacks against the UN mission, Malian military and civilians are still frequent.