Forensic experts have confirmed that human remains found at the old Pentridge Prison site in Melbourne are those of notorious Australian bushranger Ned Kelly.

After an exhaustive 20-month investigation, scientists and doctors today revealed that an almost complete skeleton found buried in a wooden axe box were those of the famous outlaw, who was executed in 1880.

Melbourne's former Pentridge Prison.

A DNA sample taken from Melbourne school teacher Leigh Olver, who is the great-grandson of Kelly's sister Ellen, confirmed the remains were those of the bushranger.

The remains at the prison had been long rumoured to be those of Kelly but never confirmed, until now.