Also on Sunday former Tiger star Kirsty Coventry earned a silver medal in the 400 women's individual medley and Matt Targett picked up a bronze for swimming on the Australian 4x100 freestyle relay team.
Auburn's total of 15 medals would have put the Tigers fourth in the country team medal count behind China (28), the United States (25) and Russia (19).
AU swimmers set three world records and 13 meet records in the eight days of competition in Rome while winning six gold medals, four silver medals and five bronze medals.
"What a great week for Auburn swimming," said Auburn head swimming coach Brett Hawke said. "For our athletes to come to an event of this scale and put on this kind of display is just huge. It really goes to show what the impact our program has had and will continue to have on this sport.
"I couldn't be more happy or proud for all of our swimmers here in Rome," Hawke added. "They all represented Auburn and what it is capable of."