The girl fell off the balcony in Girona, northwestern Spain, on Thursday while attempting to take a photo of herself on her mobile phone.
She was rushed to Josep Trueta hospital, where she remains in a "serious condition" police sources told Europa Press.
She was on the top floor of the building when she stepped on a false ceiling and plummeted towards the ground. Her fall was broken by a pile of rubbish.
The girl is badly bruised and has sustained injuries to her lower back but is reported to be in stable condition.
It is not the first serious accident that has been caused by people taking selfies.
Italy has seen a spate of selfie-related deaths, including a German tourist who fell to his death while attempting to take a photo of himself in the mountains and an Italian teenager who slipped while taking a selfie on a cliff and plummeted to the rocks 20 metres below.
Another Italian teen ended up in a coma after falling from a fence outside Rome's Colosseum while attempting a selfie, and a priceless statue was left literally legless after a foreign student attempted to take a selfie with the artwork, but ended up damaging it.