Memphis Fire Department Lt. Keith Staples said firefighters don't yet know the exact ages or genders of the victims.
Also, two teens and an 11-year-old boy sent to hospitals with burns were in stable condition, he said. Firefighters aren't sure how the three were able to escape the house, he said.
The cause of the fire that broke out about 5:30 a.m. is not yet known.
Firefighters were continuing to investigate the scene in the low-income Orange Mound neighborhood of the city.
The top portion of the home was wood-framed and most heavily damaged. The bottom is brick.
Staples said the bodies were all found in the same area on the first floor at the rear of the house. The bodies all appeared to be seriously burned.