The actor's spokesperson confirmed he died days after it was revealed he was critically ill in hospital.
The actor, who is best known for playing Walford’s bad boy Dirty Den Watts, was flown back from Bulgaria to be cared for by doctors in the UK after falling ill with a mystery illness.
A statement from his representative was released this morning, saying: "We formally announce the loss of Leslie Grantham, who passed away at 10.20am on the morning of Friday 15th June 2018.
"His ex-wife and sons have asked for their privacy to be respected at this difficult time.
"There will be a private funeral which will be attended by close family and friends only."
It is not yet known illness Leslie was suffering from, or his cause of death.
Leslie Grantham as Den Watts (Image: BBC)
He is survived by his three sons, Spike, Jake and Danny.
Leslie moved out of the UK in 2015 after splitting from his wife Jane Laurie after 31 years of marriage, setting up home in Bulgaria.
While here he starred in a Bulgarian show called The English Neighbour, playing the role of an ex-pat called John.
But it's his work on EastEnders that will remain Leslie's true legacy.
He appeared in the first episode of the BBC soap in 1985, and spoke the first line in the soap.
His character, 'Dirty' Den Watts was central to several iconic EastEnders storylines, including getting his daughter's best friend pregnant at 16, being assassinated by a crook hiding behind a bunch of daffodils in 1989.
In 1986 more than half the population - 30 million people - tuned in to the Christmas special to watch Den present his long suffering alcoholism wife Angie with divorce papers after she faked cancer to stop him leaving her.
Den returned from the dead in 2005 and was written out of the show in 2007 after a tabloid expose saw him bitterly criticise his soap colleagues to an undercover reporter on webcam.
His personal life was just as colourful as any Walford local's, too.
Leslie was convicted of murder in 1966 and served ten years in prison after a taxi robbery in Berlin went wrong.
In 2006 he appeared on Jeremy Kyle, where he shared his regrets at losing his job on EastEnders.
He said: "Of course I have regrets, but you can’t go round wearing a hair shirt all your life, otherwise you’ll never get out of bed in the morning.
"I f***ed up, now I’m going to move on."
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