In a statement issued in Nigeria's city of Maiduguri, Kamarudeen Adegoke, the MNJTF spokesperson, said the militants were killed in 30 separate encounters in recent weeks, reports Xinhua news agency.
Adegoke said an increasing dependence on improvised explosive devices (IEDs) by the insurgents was noted and necessary countermeasures were proffered.
"About four IED-making factories were destroyed in the course of the operations so far," he said.
Adegoke said over 52,000 militants and their families have so far surrendered.
At least six MNJTF soldiers and a member of the civilian joint task force were killed during the operations, he said.
"Several troops have also been injured but are recuperating well."
The MNJTF is a joint military effort created by countries including Cameroon, Chad, Niger, Nigeria and Benin to fight Boko Haram and the Islamic State's West Africa Province, which threaten the stability of the Lake Chad region.