A second woman, also 24, was shot but not seriously injured in the incident on Kilburn High Road in the early hours of Saturday morning.
Police were called to the scene at 4.20am this morning, after responding to reports of gunshots. Both woman were taken to hospital were one of them later died.
The identities of the two women have not been officially released at this stage. Although rumours are circulating online that one of the young women had been celebrating her birthday at a local club before she was gunned down.
No arrests have yet been made and a post-mortem examination will be arranged in due course. Officers from Operation Trident, which investigates gang crime and shootings in London, were also at the scene.
The death will be investigated by detectives from the Homicide and Major Crime Command.