The blaze was reported to emergency services at around 11.30pm on Saturday at a property on Glebe Road, St Andrews, Fife.
The body of a woman was found inside the house and the police and fire services are carrying out a joint investigation to establish the full circumstances.
A Police Scotland spokeswoman, said: “Police in St Andrews were called to a fire in Glebe Road, St Andrews, on Saturday around 11.30pm.
“The body of a woman was discovered within.
“Inquiries are at an early stage.
“There are not thought to be any suspicious circumstances at this time.
“A report will be submitted to the procurator fiscal.”
A Scottish Fire and Rescue Service spokeswoman, said: “We were alerted at 11:22pm on Saturday October 15 to a fire at a house in Glebe Road, St Andrews.
“Firefighters extinguished the fire using two hose reels and two covering jets.
“The body of a woman was located within the property and firefighters ensured that the property was made safe.”