Milat (74) died at Long Bay Hospital at 4.07am on Sunday, Corrective Services NSW said in a statement. Milat had been undergoing chemotherapy since first being diagnosed in May.
The former road worker was sentenced in 1996 to seven consecutive life sentences for murdering seven backpackers whose bodies were found in makeshift graves in NSW's Belanglo State Forest in the 1990s.
Milat timeline
EARLY LIFE
* Ivan Robert Marko Milat born in Sydney on December 27, 1944, the fifth of 14 children.
* He served time in a juvenile correction centre and prison for relatively minor charges.
* In 1974, he was cleared of raping one of two young hitchhikers he picked up three years earlier near the same highway where the seven murdered backpackers were picked up.
MILAT'S VICTIMS AND THEIR REMAINS
* Melbourne couple James Gibson and Deborah Everist, both 19, are last seen in inner-Sydney in December 1989 after planning to hitchhike. Their skeletal remains are found in Belanglo State Forest in October 1993.
* German backpacker Simone Schmidl, 20, vanishes while hitchhiking from Sydney to Melbourne in January 1991. Her remains are found in the forest in November 1993.
* German backpackers Gabor Neugebauer, 21, and Anja Habschied, 20, disappear from Kings Cross having planned to hitchhike from Sydney to Darwin in December 1991. Their remains are found in November 1993.
* British backpackers Caroline Clarke, 21, and Joanne Walters, 22, leave a Kings Cross hostel in April 1992. Their bodies are found in the forest in September 1992.
THE ONE WHO GOT AWAY
* British backpacker Paul Thomas Onions flees from a driver with a gun near the turn-off to the forest on January 25, 1990. He gives a description of his assailant to police on the day of the attack but only identifies Milat as that man from 13 photographs shown to him by police four years later.
THE TRIAL
* Police raid a home in Eagle Vale, on the outskirts of Sydney, on May 22, 1994 and arrest Milat.
* He is charged with seven counts of murder and one count of kidnapping Mr Onions.
* He is found guilty of all charges in July 1996 and jailed for life.
* Both the crown and defence agree the murderer is a Milat.
* Prosecutor Mark Tedeschi, QC, says the evidence points to Ivan Milat being the killer although it is likely he didn't act alone.
* Defence barrister Terry Martin argues it is a reasonable possibility it was his brother Richard, perhaps aided by another sibling Walter or a friend.
WHO SAID WHAT
* Mr Tedeschi tells the jury up to 40 features relating to Milat matched the description Mr Onions gave of his attacker.
"It is my submission there is only one person in the whole of Australia who matches all of those descriptions - the man, the car, the equipment and the place - and that is the accused," he said.
Submitting that the killer was not Ivan Milat acting alone or in company, Mr Martin suggests one or two of his brothers could have planted items, including gun parts linked to some murders, at his house.
"Do you think a person capable of these most brutal of crimes would give two hoots about planting gear on a brother?" he asked.
* In a quivering voice, the trial judge Justice David Hunt jails Milat for life on the day of the verdicts.
"These seven young persons were at the threshold of their lives, with everything to look forward to - travel, career, happiness, love, family, and even old age," he said.
