Police have launched a murder investigation after the victim, believed to be in his thirties, was found with critical injuries outside Queensbury Tube station.
Another man, aged in his 20s, is in hospital after also suffering from a gun shot wound.
Scotland Yard said officers were called to the scene on Cumberland Road at just after 9pm on Tuesday.
They found the older man with serious injuries and he died at the scene almost an hour later.
The younger man attended a north London hospital at about 9.10pm, and remains in a stable condition.
A crime scene remains in place on Cumberland Road and Essolado Way, where police say the attacks are believed to have taken place.
Officers are examining CCTV footage in the area.
Detective Inspector Justin Howick, of the Metropolitan Police, said: “I would like to appeal to anyone with information to contact police at the earliest opportunity.
“Detectives are busy at the scene and working to build a clear picture of the circumstances of this fatal attack.”
No arrests have been made and police are in the process of informing the victim’s next-of-kin.
Formal identification and a post-mortem will take place in due course.