The fire broke out just after 12 a.m. Friday. A passerby saw smoke coming from the home in the 600-block of Prospect Boulevard and called 911.
The woman was found unconscious inside. She died at the hospital. Elgin police identified her as Josephine Guerra.
There was no word on what caused the fire.
Police say Guerra was alone in the home. Her husband was out of state when the fire occured.