Wales had no answer to the pace, power and ball-playing skills of Fiji, with Suliasi Vunivalu scoring a hat-trick of tries and 10 different players claiming touchdowns.
The Welsh players travel to Perth for their final match against Ireland who lost 14-6 against Papua New Guinea.
They will be hoping to win a first match at the world cup since 2000.
Fiji: Kevin Naiqama (capt), Suliasi Vunivalu, Taane Milne, Akuila Uate, Marcelo Montoya, Jarryd Hayne, Henry Raiwalui, Ashton Sims, Apisai Koroisau, Eloni Vunakece, Viliame Kikau, Salesi Faingaa, Tui Kamikamica, Joe Lovodua, Jacob Saifiti, Junior Roqica, Ben Nakubuwai.
Wales: Elliot Kear, Rhys Williams, Michael Channing, Christiaan Roets, Regan Grace, Courtney Davies, Danny Ansell, Craig Kopczak (capt), Steve Parry, Philip Joseph, Rhodri Lloyd, Joe Burke, Morgan Knowles, Matty Fozard, Matthew Barron, Ben Evans, Dalton Grant.
Referee: Chris Kendall (England).
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