Greek-Australian dual national, Perry Kouroumblis, 65, faces two counts of murder and one count of rape, almost 50 years after they died.
He arrived in Melbourne on Tuesday night after being extradited from Italy, marking the first time in about eight years he has set foot on Australian soil.
He was interviewed by Victoria Police, charged, and is due to face Melbourne Magistrates Court on Wednesday afternoon.
Kouroumblis was arrested at Rome's Leonardo Da Vinci Airport in September over the alleged slaying of Suzanne Armstrong, 28, and Susan Bartlett, 27, in January 1977.
Suzanne Armstrong (right) and Susan Bartlett were murdered in in 1977. (HANDOUT/VIC POLICE)
Dubbed the "Easey Street murders", the friends were found dead with more than two dozen stab wounds in their home on Easey Street in Collingwood in Melbourne's inner north.
Ms Bartlett's 16-month-old son Gregory was found unharmed in his cot.
Ms Armstrong and Ms Bartlett were last seen alive on January 10, 1977, and their bodies were found three days later.
The women went to school together at Benalla in Victoria's north.
Victoria Police Chief Commissioner Shane Patton has described their murders as "an absolutely gruesome, horrific, frenzied homicide".
He said it was one of Victoria's "most serious cold case and longest cold case".
"There is simply no expiry date on crimes that are as brutal as this," he said.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
18°C