A woman was taken to hospital on Thursday (26 May) afternoon after being hit by a train in Kilburn High Road.
Emergency services were called to the scene around 1.07pm and was treated at the station.
The north west London station was closed to the public until London Air Ambulance medics treated her.
A spokesperson for London Air Ambulance told getwestlondon: "We sent a number of resources including an ambulance crew, an incident response officer, our hazardous response team and London's Air Ambulance.
"We treated a woman at the scene for head and leg injuries and took her as a priority by road ambulance to a major trauma centre in Central London."
A British Transport Police spokesperson said: "We were called to Kilburn High Road station at 1.07pm following reports of a person being struck by a train.
"A woman was treated for injuries at the scene before being taken to hospital in a serious condition.
"The incident is not being treated as suspicious."
It was the second such incident in west London in the space of three days, with an incident in Twickenham caused a fatality on Tuesday (May 24).
