A 24-year-old man was found stabbed to death in Hounslow in the early hours of Tuesday.
The Metropolitan Police were called at roughly 1.15am to reports of a stabbing in Grove Road.
Officers found a man with stab wounds and despite the efforts of the emergency services he died at the scene.
His family have been informed and are being supported by specially trained officers, Scotland Yard said in a statement.
No arrests have been made and a post mortem examination is expected to be carried out in the coming days.
Chief Superintendent Sean Wilson, responsible for policing in west London, said: "It is tragic that another young man has lost his life in a stabbing. My thoughts are with his family and friends.
"Officers in Hounslow are supporting the murder investigation and I would encourage anyone who knows anything about the circumstances of this incident to contact us immediately."
