In addition to his NBL career, Ronaldson represented Australia at international level on numerous occasions, making his debut for the Boomers at the 1994 FIBA World Championship in Toronto, Canada. He was also a member of the Boomers for the 1996 Olympic Games (in which he made a spectacular four-point play in the dying seconds against Croatia to give the Boomers a 73–71 win and a berth in the bronze medal game against Lithuania where they lost 80–74), the 1998 FIBA World Championship in Greece, the 2004 Olympic Games and the 2006 Commonwealth Games in Melbourne where he won a gold medal with the Boomers after they easily defeated their Trans-Tasman rivals New Zealand 77–39 in the Final.