The victim, named by police as Ali Nasrollahi, 22, was found collapsed in Barnet on Tuesday afternoon.
Mr Nasrollahi, who was found at the junction of Woodside Grange Road and Grangeway, was treated by paramedics for a single stab wound but died soon after arriving at hospital.
Police have launched a murder inquiry and have appealed for witnesses to come forward. No arrests have been made.
Det Insp Julie Willats said: "We know that the victim had driven to Woodside Grange Road with one of his friends and met up with another friend, who had also driven there.
"At some stage, the victim interacted with a group of up to four suspects, during that interaction we believe he was stabbed.
"The group of suspects then ran off down Grangeway and into an alleyway that leads on to Woodside Avenue."
The victim's friend Mohamed Musalam said: "I'm shocked... I had to call 10 people to confirm because it was just unreal.
"He didn't deserve it at all, he wasn't that sort of a person where he hangs around with the wrong crowd or anything like that.
"He was a happy guy, the sort of guy that comes into a group and makes everyone laugh. I am heartbroken."
Officers are carrying out a forensic search in the area.

Officials have confirmed that of the 184 inmates that escaped, 70 have been captured, leaving 114 still at large.
Among those on the run is Brayan Bremer, who posted pictures of himself on the run on social media.
About 100 federal officers have been sent to Amazonas to boost the search.
Amazonas governor Jose Melo requested the help of the federal government on Sunday, saying Amazonas were "at their physical and psychological limit".
The prisoners escaped from the Anisio Jobim jail in Manaus and the neighbouring Antonio Trindad prison as a deadly riot was under way in the former.
Brazil prison riots: What's the cause?
The director of the Anisio Jobim jail, Jose Carvalho da Silva, has since been suspended over allegations he took money from the Familia do Norte gang in exchange for turning a blind eye to drugs and weapons beings smuggled into the jail.
Investigators say the Familia do Norte instigated the riot and specifically targeted members of rival gang First Capital Command (PCC).
Mr Silva is also accused of allowing inmates to flee the prison in exchange for money.
He had been put in charge of the jail on 28 December in an interim capacity, after serving as deputy head.
Two inmates made the allegations against him in separate letters sent to the authorities three weeks before the riot.
In the letters, the inmates say that Mr Silva had threatened to move them from a secure area of the jail into a "general population" area, even though they had received death threats and a judge had ordered they be kept separate from the general prison population.
The two were among the 56 inmates killed during the riot on 1 January.
A man has been stabbed to death in a street in north London.
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Police in Brazil are stepping up their search for more than 100 prisoners who are still on the run after escaping from adjoining prisons in the northern state of Amazonas on 1 January.