Police were called to the A406 at the junction with Neasden Lane at 5.51am on Friday (August 18) finding a HGV in collision with a pedestrian.
London Ambulance Service also attended the incident but the 45-year-old male pedestrian was pronounced dead at the scene.
The driver of the HGV stopped and has been helping police with enquiries.
Next of kin have been informed but police say formal identification has yet to be completed and a post mortem examination will take place in due course.
Officers from the Met's Serious Collision Investigation Unit are investigating and currently no one has been arrested in relation to the collision.
Police are urging anyone with information to contact detectives on 020 8991 9555 or via Twitter @MetCC.
Those wishing to pass on information anonymously can do so by calling Crimestoppers on 800 555 111 or online.
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