This was one of the rare official death toll a few weeks before presidential elections in which security is a big issue.
Defence spokesman Major-General Chris Olukolade was reacting to reports that some 2,000 had been killed by Boko Haram insurgents who took control of Baga and the surrounding area 10 days ago. The military is fighting to reclaim it.
(READ MORE: Suspected boko haram gunmen kidnap over 100 women, children in Nigeria)
Scores of civilians were killed when the militants, who are fighting to establish an Islamic state in northern Nigeria, raided Baga and a nearby military base. The base is also the headquarters of a multinational force with troops from Chad, Niger and Cameroon.
Witnesses who escaped to neighbouring towns and Borno state capital Maiduguri said the insurgents razed buildings and homes and killed dozens of civilians in subsequent raids last week.
Thousands of refugees have fled Baga to neighbouring Chad or been displaced within Nigeria.
"Terrible atrocities have been committed against innocent Nigerians in Baga by the rampaging terrorists who attacked and have been operating in the town since 3 January," Olukolade said at a news conference.
(READ MORE: Insight: boko haram exploits Nigeria’s slow military decline)
"From all available evidence, the number of people who lost their lives during that attack has so far not exceeded about 150 ... including ... terrorists who were bearing arms and got killed in the course of ... battle with troops."
The military has a habit of understating death tolls, while local politicians tend to overstate them.
"Many residents have left, leaving the population in the town almost seriously depleted," Olukolade said.
Boko Haram has killed thousands in a five-year-old rebellion which is seen as the biggest security threat to Africa's top oil producer and is a headache for President Goodluck Jonathan ahead of what is likely to be a closely fought vote on Feb. 14.
A southern Christian, he faces Muhammadu Buhari, a northern Muslim and former military ruler regarded as tough on security.