Fire crews received an emergency call at around 9:55pm on Monday and arrived at the scene in East Kilbride in less than five minutes.
It is understood that a neighbour made the emergency call after smelling smoke and hearing an alarm sounding in the house on Shiel Avenue.
The woman was rescued from the burning house by firefighters and was treated for smoke inhalation by paramedics on site, before being taken to nearby Hairmyres Hospital.
A fire service spokesman said: "Firefighters reached the scene in around four minutes and the incident commander immediately committed a team in breathing apparatus to search the property and tackle the flames.
"They recovered an elderly woman, ensured no-one else was inside the property and extinguished the fire with a high pressure water jet."