Armed police were called to Green Lanes, N15 at 11.15pm to a report of a teenager shot.
A 17-year-old boy was taken to hospital with a gunshot wound, he is in a life-threatening condition.
Officers from Trident are investigating. No arrests have been made.
A Section 60 has been implemented across all of #Haringey borough until 06:00hrs on Thursday, 5 December.