The attack also injured 20 people, of which four are in serious condition, said Olivier Salgado, spokesman for the UN mission in Mali known as MINUSMA.
No one claimed responsibility for the attack in the country's restless north but Islamic extremists are suspected. In 2013, the French pushed Islamic militants out of Mali's northern cities and towns although jihadists continue to carry out attacks on UN peacekeepers.
"I want to reiterate that these attacks will not impede the determination of the United Nations to support the Malian people and the peace process," said Mongi Hamdi, the head of the UN mission and the special representative for the secretary-general in Mali.
Northern Mali has been unstable since it fell to Tuareg separatists and Islamic extremists following a military coup in 2012. Despite the presence of French troops and the UN force, the extremists have continued attacks in the north.
Extremists have also extended attacks farther south this year, including an assault on a Bamako restaurant/nightclub popular with foreigners in March and a Nov. 20 attack on a luxury hotel in the capital.