A spokesman for North Yorkshire Police said: Officers attended an address on the High Street, Starbeck, at 3.25pm on Thursday 4 September 2014, following a report that a man had fallen from a window.
On arrival the officers found an 18-year-old year local man who had suffered serious injuries.
He has been taken to Leeds General Infirmary by air ambulance.
We are not in a position to give any further details about his condition at this time.
There are not believed to be any suspicious circumstances and no one else is being sought in connection with the incident at this time.
Anyone who witnessed the incident should contact North Yorkshire Police on 101 and pass the information to the Force Control Room.