Bailie fought through tough conditions including heavy winds, to finish in a time of 56 minutes, 50.18 seconds across the 5km run, 20km cycle and 2.5km run course.
It was the 22-year-old’s first race in his home state since the Rio Olympics where he finished 10th in the triathlon.
“It was great to race back in Perth, it’s always special to race in front of a WA crowd,” Bailie said.
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Despite heavy winds, Bailie was in exceptional form and was able to shrug off strong cyclist Matthew Burton in the final run leg despite coming off the bike leg and into the transition area at the same time.
More than 600 competitors participated in the event as part of their bid for Australian Champion Status and selection into the 2017 Australian World Duathlon Team.
Paralympian Brant Garvey also took part in the event.