Samuel was born inΒ Hamilton, Victoria, the son of Maree and Clifford Samuel.Β He grew up inΒ Adelaide, South Australia and graduated fromΒ Rostrevor CollegeΒ in 2001. He has a younger brother,Β Benedict, a writer, producer and actor,Β as well as an older sister, Bridget, a stage manager. Despite completing his senior secondary years atΒ Rostrevor College, Samuel undertook final year drama atΒ Christian Brothers CollegeΒ under the tutelage of Amanda Portus, where he played the part of Tom Snout (the wall) in Rostrevor College's production of Shakespeare'sΒ A Midsummer Night's DreamΒ as well as playing "Belvile" in CBC's production ofΒ Aphra Behn'sΒ The RoverΒ (The Banished Cavaliers). Xavier Samuel later attended Flinders University Drama Centre in 2005, where he studied under renowned acting teacher Professor Julie Holledge. He playedΒ HamletΒ in the graduate production.