The 87-year-old went to put out the fire but then fell over and banged his head on his way out at 6.15pm today.
He was helped by four men who were passing the property on Yarrow Place, Leyland, until the fire service arrived.
The pensioner was taken to hospital for treatment to his head injury and smoke inhalation.
A neighbour also suffered smoke inhalation.
Firefighters from Leyland and Bamber Bridge put out the blaze, which damaged the chip pan but did not spread.