The explosion happened at 14:30 GMT on Thursday as the vehicle was escorting a "logistical convoy", on the road between Tessalit and Aguelhok.
A statement by the United Nations mission in Mali (MINUSMA) said the two wounded peacekeepers were brought to the city of Kidal for treatment.
It did not specify the nationalities of the peacekeepers.
"I condemn in strongest terms such abject acts, whose only objective is to destabilise the country and harm the peace process under way in Mali," Koen Davidese, interim chief of mission, said.
He said the UN mission is "determined" to pursue all efforts to bring peace to the country.
Such a deadly attack, Davidse said, could be considered as an international war crime.
In a post on social media, Jean-Pierre Lacroix, undersecretary-general for UN peacekeeping, expressed his "thoughts and compassion" to the victims, their families and colleagues.
There was no immediate claim of responsibility for the attack.
But armed groups once affiliated with al-Qaeda, such as the Jamaat Nusrat al-Islam wal-Muslimeen, have in the past carried out assaults in the region.
In September, three peacekeepers from Bangladesh were killed and five others were seriously wounded when their convoy came under attack in the Gao region just south of Kidal.
Since 2013, when MINUSMA was deployed in Mali, there have been more than 80 peacekeepers killed, making the the mission the deadliest in the world.
Mali's neighbouring countries such as Niger, Chad, Mauritania and Burkina Faso have also been fighting armed groups in the Sahel region.
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