The girl's mother noticed the smoke in time and was able to evacuate all three of her children from their home in Hallein im Tennengau, in Salzburg on Wednesday night.
Earlier that evening her nine-year-old daughter had lit a cigarette in an attic bedroom and was smoking it in her bunk bed. She stubbed it out on her bedroom wall and left the glowing butt in her bed after she went to sleep in her mother's room, along with her siblings aged two and 11.
Her older brother was woken at around 11pm by a strong smell of burning. He immediately woke his mother up - who discovered thick clouds of smoke coming from the empty attic bedroom.
She roused her children and grabbing the family's two cats left the apartment and called the fire brigade. Firemen were able to control the blaze and quickly extinguish the flames.
When they examined the charred remains of the children's bedroom they found a melted lighter and mobile phone.
The guilty nine-year-old then admitted she had been smoking a cigarette. Luckily no one was injured in the fire but police said the damage to the apartment is considerable.