Alfie Evans, the 23-month-old toddler whose grave illness drew international attention, died early on Saturday, his father said in a Facebook post.
Tom Evans said he was 'heartbroken' by his son's death.
Announcing the news on Facebook on Saturday, Alfie's parents, Tom Evans and Kate James said: 'Our baby boy grew his wings tonight at 2:30am. We are heart broken. Thank you everyone for all your support.'
Alfie had a rare, degenerative disease and had been in a semi-vegetative state for more than a year.
After a series of court cases Alder Hey Children's Hospital in Liverpool, northern England, removed his life support on Monday, against his parents wishes.
He confounded expectations by continuing to breathe unaided.
Medical experts in Britain had agreed that more treatment would be futile, but his parents wanted to take him to Rome, where the Vatican's Bambino Gesu hospital had offered to care for him.
The case has provoked strong feelings over whether judges, doctors or parents have the right to decide on a child's life. Alfie's parents have been backed by Pope Francis and Poland's President Andrzej Duda.
Alfie's death came after Charlie Gard's parents, whose campaign to save their own terminally ill baby spread around the world last year, called for a change in the law to give parents more control over the care of their sick children.
Chris Gard and Connie Yates said they had watched Alfie Evans' case with a 'heavy heart' and said it is 'impossible to understand the pain' parents Tom Evans and Kate James are going through.
They joined calls for a change in a law that currently demands courts take the child's 'best interests' as the 'gold standard' rather than the parents' wishes when ruling on how terminally ill children should be treated.
Cases such as Charlie Gard's and Alfie Evans' are judged on what is best for the patient's welfare, rather than giving priority to what the parents think.
Ruling in the Charlie Gard case, Lord Justice McFarlane said: 'The sole principle is that the best interests of the child must prevail and that must apply even to cases where parents, for the best of motives, hold on to some alternative view.'
Charlie Gard went on to die on July 28 last year and his parents have now launched a campaign to change the law.
Additional reporting by Reuters.
