Kyle McDonald has been named as the teenager gunned down on a residential road in Battersea on Wednesday night.
The 19-year-old, from Fulham, was shot dead in Coppock Close.
Scotland Yard has launched a murder investigation and is appealing for witnesses.
Police and London Ambulance Service were called shortly after 7.50pm following reports of an injured man. He was pronounced dead at the scene at around 8.15pm.
Police said they were keeping an "open mind" over the motive and circumstances of the shooting.
The teenager's next of kin have been informed and a post-mortem examination will be held later.
Police are appealing for witnesses and an incident room has opened under Detective Chief Inspector Matt Bonner of the Homicide and Major Crime Command.
He said: "We are still in the early stages of the investigation and are carrying out a number of inquiries into the circumstances of this incident.
"I am keen to establish if there was anyone in the area who saw or heard anything suspicious yesterday evening.
"I'm appealing for anyone who has any information no matter how small to please come forward and help us with our inquiry".
Anyone who witnessed the shooting or has information that may assist police is asked to contact detectives on 0208 358 0200, or Crimestoppers anonymously on 0800 555 111.