Constantinos "Costas" Kilias () is a Greek Australian magistrate and actor.
Kilias is the son of Greek immigrants who arrived in Australia in 1954, from the town of Kolindros, in the region of Macedonia in Northern Greece.
After graduating from the University of Melbourne in the early 1980s, Kilias was admitted to the Victorian Bar in 1986.
Kilias currently works as a magistrate in Melbourne.
Kilias is best known for his role as Farouk in The Castle (1997), as well as Tony the Yugoslav in The Wog Boy (2000) and ' (2010). He also had roles in Fat Tony & Co. (2014) as the Head of Hellenic Anti Drug Dept and in the film The Wannabes (2003) as Adrian. He also appeared in some episodes of Fat Pizza (2003).