Soldiers from Chad killed 207 Boko Haram fighters in clashes near a Nigerian town close to the border with Cameroon, Chad's army announced in a statement.
One Chadian soldier was killed and another nine were wounded in Gambaru, the scene of regular attacks by the group in recent months. There was no immediate independent verification of the Chadian army's announcement, reports Reuters news agency.
Chad's military also claimed to have seized large quantities of small arms and ammunition and two pick-up trucks on Tuesday.
Niger, Cameroon and Chad have launched a regional military campaign to help Nigeria defeat the Boko Haram insurgency, which aims to carve an Islamic emirate out of northeastern Nigeria.
Chad deployed troops last month in support of Cameroonian efforts to stop repeated cross-border raids by the fighters, whose operations increasingly threaten Nigeria's neighbours.
The African Union last month authorised the creation of the regional force, which will also include Benin, and is pushing for a United Nations Security Council mandate for the operation.