MINUSMA, the UN's peacekeeping mission in the volatile west African nation, said the vehicle, part of a logistics convoy, hit the explosive device some 70 kilometres (40 miles) east of the small town of Ansongo.
"The explosion destroyed the vehicle and seriously injured two MINUSMA soldiers who are being medically evacuated," MINUSMA said in a statement.
The UN says 56 peacekeepers have been killed in combat since MINUSMA's inception in 2013, making northern Mali the deadliest theatre on earth for its personnel.
The vast desert region has been a cauldron of unrest since an uprising by the nomadic Tuareg people in 2012 allowed Al-Qaeda-linked militants to seize Mali's vast desert north.
Small pockets of armed extremists remain active, carrying out occasional attacks, and the region has also seen clashes between Tuareg rebels and pro-government militants despite a peace accord.