The MINUSMA peacekeepers were withdrawing from the military base in the rebel stronghold of Kidal over the weekend.
"On Saturday, the convoy encountered two other improvised explosive devices near the town of Anefis," Stephane Dujarric, a spokesperson for the UN secretary-general, told reporters on Monday.
He said that "22 peacekeepers had to be evacuated by air to receive immediate treatment in Gao."
It was the sixth such incident since the peacekeepers began leaving their base in Kidal on October 31, bringing the total number of peacekeeprs injured in the convoy to 39.
JNIM, an extremist group with links to al-Qaida, claimed responsibility for the two earlier attacks.
MINUSMA pulling out of Mali
After this, the UN Security Council terminated the mission's mandate on June 30 and the UN began what Secretary-General Antonio Guterres called an "unprecedented" six-month exit from Mali by December 31.
An alliance of largely Tuareg rebels in northern Mali recently resumed attacks against the Malian state. The rebels claim to have taken over the Kidal camp shortly after MINUSMA left.
The peacekeepers' final departure had originally been scheduled for late November but this was pushed forward after a deterioration in the security situation.
The UN mission's accelerated withdrawal reportedly angered the Malian junta, whose forces had not yet reached the camp.
zc/lo (AFP, AP)