The incident occurred at Brearton and the emergency services were alerted by concerned neighbours at 10.09pm on Saturday.
Despite the efforts of firefighters and paramedics to save her life, a woman aged in her late 60s died at the scene. Her family are being supported by the police.
Firefighters had to put the blaze out and ventilate the smoke-filled property.
There were no other occupants, and no neighbouring properties were damaged.
As part of the joint investigation to determine the cause of the fire, police are asking people to come forward with any information that could help the inquiry.
If you can help, please contact North Yorkshire Police on 101, select option 1, and speak to the Force Control Room. Please quote reference number 12220056029 when providing details.
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