A tweet by France's National Police said the SWAT team assault dog named Diesel was "killed by terrorists" during the raid in Saint-Denis, north of Paris.
The death of the 7-year-old dog was confirmed at 11:40 a.m. Paris time, about seven hours after the raid began.
Two suspects died in the assault, one of them a female suicide bomber. Seven people were arrested.
Several police officers were slightly injured.
The Associated Press contributed to this report.