| | Event type
400 metres, Boys
| Date | 11 – 14 October 2018 | |
|---|---|---|
| Status | YOG | |
| Location | Athletics Field, Parque Olímpico de la Juventud, Villa Soldati, Buenos Aires | |
| Participants | 26 from 26 countries | |
| Format | Two stages with final results determined by cumulative time. | |
| Pos | Nr | Athlete | NOC | Time | Stage One | Stage Two | |||
|---|---|---|---|---|---|---|---|---|---|
| 1 | – | Luis Avilés |  MEX | 1:34.23 | 47.45 (1) | 46.78 (2) | Gold | ||
| 2 | – | Kennedy Luchembe |  ZAM | 1:34.34 | 47.98 (4) | 46.36 (1) | Silver | ||
| 3 | – | Nicholas Ramey |  USA | 1:34.87 | 47.60 (2) | 47.27 (3) | Bronze | ||
| 4 | – | İlyas Çanakçı |  TUR | 1:35.78 | 47.96 (3) | 47.82 (4) | |||
| 5 | – | Lorenzo Benati |  ITA | 1:36.58 | 48.58 (6) | 48.00 (5) | |||
| 6 | – | Bernat Erta |  ESP | 1:37.31 | 49.18 (9) | 48.13 (6) | |||
| 7 | – | Dilan Bogoda |  SRI | 1:37.33 | 48.52 (5) | 48.81 (9) | |||
| 8 | – | Solomon Diafo |  GHA | 1:37.55 | 49.08 (8) | 48.47 (7) | |||
| 9 | – | Keegan Bell |  AUS | 1:38.63 | 49.58 (10) | 49.05 (11) | |||
| 10 | – | Yefim Tarasov |  KAZ | 1:38.81 | 48.93 (7) | 49.88 (12) | |||
| 11 | – | Douglas Mendes da Silva |  BRA | 1:39.04 | 50.39 (12) | 48.65 (8) | |||
| 12 | – | Junior Rouse |  SKN | 1:40.70 | 50.33 (11) | 50.37 (14) | |||
| 13 | – | Raymond Oriakhi |  BAH | 1:41.02 | 51.01 (15) | 50.01 (13) | |||
| 14 | – | Bernard Olesitse |  BOT | 1:41.08 | 52.04 (18) | 49.04 (10) | |||
| 15 | – | Wang Yu-Hsuan |  TPE | 1:41.36 | 50.82 (14) | 50.54 (15) | |||
| 16 | – | Gnanzou Desire Kodjo |  CIV | 1:41.58 | 50.47 (13) | 51.11 (17) | |||
| 17 | – | Evaldo Whitehorne |  JAM | 1:42.48 | 51.55 (16) | 50.93 (16) | |||
| 18 | – | Potchara Petchkaew |  THA | 1:43.00 | 51.81 (17) | 51.19 (18) | |||
| 19 | – | Christel Rakotomalala |  MAD | 1:47.19 | 54.31 (20) | 52.88 (20) | |||
| – | Yusuf Anan |  BRN | – | – ( | 52.37 (19) | ||||
| – | Dalitso Gunde |  MAW | – | 53.88 (19) | – ( | ||||
| – | Ludovic Oucéni |  FRA | – | 58.15 (21) | – ( | ||||
| – | Malik John |  IVB | – | – ( | – ( | ||||
| – | Jared Sylvester |  GRN | – | – ( | – ( | ||||
| – | Clevonte Lodge-Bean |  BER | – | – ( | – ( | ||||
| – | Berat Mustafa |  MKD | – | – ( | – ( |