The incident happened in Brixton Road near Coldharbour Lane at around 5.10am today (March 20).
Officers and London Ambulance Service crews attended and found a man who had been stabbed.
He was pronounced dead at the scene shortly after.
Officers hope to speak to people who were in the area at the time between 4.45am and 6am, who may have seen something,
An appeal has launched calling for anyone with information to come forward.
Detective Chief Inspector Brian Howie, from the Met’s Specialist Crime Command and leading the investigation, said: “My thoughts are with the victim’s family and friends at this devastating time.
“I understand the shock and concern this incident will have on the Brixton community.
“My team are already working diligently to gather evidence and establish what led to this tragedy. I would ask any local residents with concerns to speak to officers at the scene, or to their local neighbourhood policing teams.
“If you have any information that could assist this investigation, I would urge you to get in contact immediately. I am particularly keen to speak to anyone who was in the area between 04.45hrs and 06.00hrs and may have seen something.”
Anyone with information that could assist police is asked to call 101 or message @MetCC on ‘X’ quoting CAD843/20Mar.
