Corporal Cirillo, 24, was gunned down as he stood guard at Canada’s war memorial on Wednesday morning.
The dad-of-one was rushed to hospital but later died of his injuries.
La Repubblica reported that Cirillo was of Italian origin, and “had a passion for animals and loved to keep fit.”
Rest in Peace Nathan Cirillo, the solider who sacrificed his life to protect and serve our country. He was only 24. pic.twitter.com/DcBI071ktT
— Cause We're Canadian (@MadelnCanada) October 22, 2014
The gunman, named as Michael Zehaf-Bibeau, then rampaged through parliament before being shot dead.
Three other people were treated in hospital for their injuries and later released.
Canadian Prime Minister Stephen Harper said the attack was inspired by the Islamic State in Iraq and Syria (Isis) militant group.