Rishmeet Singh is the 28th teenager to be killed in London this year.
A 16-year-old boy who was fatally stabbed in west London has been named.
Rishmeet Singh was attacked in Raleigh Road, Southall, just after 21:00 GMT on Wednesday. Emergency services attended however he died at the scene.
The Met Police said they were called following reports of a fight. No one has been arrested.
Ch Supt Sean Wilson said Rishmeet’s family were devastated. He added specialist detectives were working “at pace” to find out who was responsible.
The head of policing for Ealing, Hounslow and Hillingdon, added: “I know that this tragic incident will have understandably shocked the local community and our officers throughout the West Area share that shock. We remain committed to working with the local community to address any concerns they may have.
“Residents across Hounslow, Hillingdon and Ealing can expect to see an increased policing presence over the coming days and I would encourage anyone who has concerns to please speak to officers.”
Rishmeet is the 28th teenager to be killed in London this year. The most recorded in one year was 29 in 2008.
A Section 35 dispersal order – which gives officers powers to direct people to leave an area – has been authorised until 14:29 on Sunday in Southall Broadway, Southall Green, the Havelock Estate, Uxbridge town centre and Hayes town centre.
Det Ch Insp James Shirley, who is leading the investigation, has appealed for witnesses or anyone with information to come forward.
He said this included those who were in the area around Raleigh Road. He also urged local residents or road users to check doorbell, dashboard or CCTV cameras which may have captured footage useful to the investigation.
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