Antonios 'Anton' Crocaris has died after the Flinders St attack.
Am 83-year-man man has died as a result of injuries he sustained last week when a vehicle ploughed into Christmas shoppers in Melbourne's central business district.
Antonios "Anton" Crocaris, of the inner-city suburb of Northcote, died in hospital about 11.30pm Friday, police confirmed in a statement.
The accused driver, Saeed Noori, 32, of Heidelberg West, has been charged with 18 counts of attempted murder and one count of conduct endangering life, but police now expect a charge of murder to be added.
Family members said Mr Crocaris was "irreplaceable".
"Our deepest gratitude to the wonderful people of Melbourne and dedicated first responders who rendered him and others every assistance. Special mention to the caring staff of The Alfred Intensive Care Unit.
"Our dad, our hero."
Mr Noori, an Afghan refugee and Australian citizen, is accused of mowing down pedestrians with his white Suzuki Grand Vitara outside Flinders St Station on the afternoon of December 21, in what police called a "deliberate act".
Police said the accused driver had a history of drug and mental health problems, and that he acted with "the intention of killing or causing serious injury".
Mr Noori appeared behind protective glass in Melbourne Magistrates Court on Wednesday where his defence lawyer argued that his mental health needed to be assessed before he could enter a plea.
A police statement tendered to court said Mr Noori's motive for the attack remained unclear.
Investigators said last week that the accused had no apparent terrorist links, but he did rant about the mistreatment of Muslims, Allah and Australian Security Intelligence Organisation (ASIO) while under police guard.
Nineteen people were hospitalised after the incident, including six who remain in hospital.
Police said they had taken a "significant number of statements" from witnesses but there were still a "large number of people" yet to be interviewed.
Officers urge anyone who may need help in coping with the traumatic incident to phone Victoria's Victims of Crime Helpline on 1800 819 817.