It happened just after 12:30 p.m. Saturday, Jan. 25 in Plainview on Audrey Avenue.
After the fire was knocked down, the body of the 65-year-old woman was found in an upstairs bedroom, Nassau County Police said.
The Plainview Fire Department, with the assistance of Jericho, Syosset and Bethpage Fire Departments extinguished the fire.
The cause of the fire has yet to be determined but it appears to non-criminal in nature, police said.
The investigation is continuing.
This is a developing story. Check back to Daily Voice for updates.
Click here to follow Daily Voice Brentwood and receive free news updates.