The boys' 4 × 100 metre freestyle relay event at the 2018 Summer Youth Olympics took place on 9 October at the Natatorium in Buenos Aires, Argentina.

Results Final The final was held at 19:30.Final results Rank Lane Name Nationality Time Notes 2 Kliment Kolesnikov (48.04)Daniil Markov (49.58)Vladislav Gerasimenko (51.56)Andrei Minakov (48.93) 3:18.11 6 Murilo Sartori (50.55)Lucas Peixoto (49.70)André Calvelo (48.87)Vitor de Souza (51.87) 3:20.99 8 Federico Burdisso (50.06)Thomas Ceccon (49.33)Marco De Tullio (50.84)Johannes Calloni (51.78) 3:22.01 4 4 Wang Guanbin (51.40)Shen Jiahao (50.52)Sun Jiajun (51.71)Hong Jinquan (50.40) 3:24.03 5 7 Ashton Brinkworth (50.79)Lewis Blackburn (51.69)Joseph Jackson (50.89)Stuart Swinburn (51.32) 3:24.69 6 5 Keisuke Yoshida (52.14)Taku Taniguchi (51.15)Shinnosuke Ishikawa (52.22)Yu Hanaguruma (51.29) 3:26.80 7 3 Will Barao (53.14)Ethan Dang (52.80)Jake Johnson (52.56)Ethan Harder (51.85) 3:30.35 8 1 Ethan du Preez (53.58)Hendrik Duvenhage (52.80)Gabriel Nortje (51.02)Michael Houlie (53.79) 3:31.19

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