Police were called to Station Road, Wood Green, at about 03:20 BST after receiving reports of a stabbing outside the Jolly Anglers public house.
Paramedics treated the man, named by police as 33-year-old Vincent Harvey, but he was pronounced dead at the scene.
No arrests have been made and the Met have appealed for witnesses.
Det Ch Insp Noel McHugh said there was "a large number of people in and around the Jolly Anglers pub at the time Vincent was stabbed".
"It is vital that anyone who saw this incident, or the events leading up to the incident, get in contact with police," he said.

Adrian Bayley was sentenced to life imprisonment in 2013 for killing Jill Meagher, an ABC Radio employee.
On Thursday, it was announced he had been found guilty of three more rapes, of a Dutch tourist and two sex workers.
The three trials were the subject of a suppression order to ensure fairness, but this was lifted after a verdict was returned in the third trial.
Bayley was described by a judge in 2013 as a "recidivist sex offender". He was on parole for previous rape convictions when he killed Ms Meagher.
Ms Meagher, originally from County Louth, was attacked in Melbourne in September 2012 as she walked home. Her body was discovered six days later buried on the outskirts of the city.
The new convictions relate to two attacks in 2012 and one in 2000.
All the women came forward after recognising Bayley during the investigation and subsequent court proceedings over the killing of Ms Meagher.
The defence argued that the women had wrongly identified Bayley because of his prominence in the media, but juries in three separate trials disagreed.

The 32-year-old, who earned his only cap for Wales in 2006, has spent time at eight clubs including Nottingham Forest, Yeovil and Peterborough.
"No matter what club you are at you have to strive to do the best you can and aim for the top," Davies said.
"Everyone will be thinking about promotion at this time of the year and we're no different."
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The 28-year-old from Ballymena needs one more victory in Rio to be sure of a medal.
It was a close contest but Donnelly, who won bronze at the Commonwealth Games in 2014, shaded it on a split decision.
He will fight world champion Mohammed Rabii of Morocco in the last eight.
That bout will take place at Riocentro on Saturday at 16:15 BST.
Thursday's contest was Donnelly's second at the Games as he outpointed Zohir Kedache of Algeria in his opening fight at Riocentro.
"There was not so much pressure on me as there was for the first fight and I think that showed in my performance," said Donnelly who finished with a badly-swollen left eye.
"I felt more comfortable as the fight went on.
"My next opponent is the world champion but I believe in myself and anything is possible at the Olympic Games.
"I have great belief in myself and am going to give it my all."
A murder investigation has been launched after a man was stabbed to death outside a busy north London pub.
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An Australian man jailed for the rape and murder of an Irish woman has been convicted of three more rapes.
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Accrington Stanley have signed former Exeter City midfielder Arron Davies on a one-year deal.
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Ireland's Steven Donnelly has beaten Tuvshinbat Byamba of Mongolia on points to reach the quarter-finals of the welterweight division at the Olympics.