Marty played for the University of New Hampshire in the 2007–08 season on defense. She scored three goals and added seven assists for 10 points along with a plus-24 rating in 31 games. Prior to her NCAA career, she played for EV Zug in the top Swiss league from 2003–07. She was an All-Star selection in 2005 and participated in the European Champions Cup, helped EV Zug to a third-place finish in 2004. She also skated for DHC Langenthal and the EHC Wettingen-Baden boys team. In a game versus Russia at the 2012 IIHF Women's World Championship, Julia Marty logged two points (one goal, one assist) in a 5–2 victory, as Switzerland advanced to the semifinals.