Johnny Furphy was born and grew up in Melbourne, Australia. He attended the Basketball Australia Centre for Excellence at the Australian Institute of Sport. During his senior season, Furphy averaged 14.3 points and 5.6 rebounds in 12 games. He committed to play basketball in the United States for the University of Kansas.
Furphy started his freshman season as a wing reserve, but as season went on he joined the starting 5. He played in 33 games, starting 19 of those contests and averaged 9.0 points and 4.4 rebounds per game.