| POS | Rank | Heat | BIB | ATHLETE | COUNTRY | RESULTS |
|---|---|---|---|---|---|---|
| 1 | 1 | 1 | USA | United States U20 |
USA |
3:32.66 Q |
| 2 | 1 | 2 | ITA | Italy U20 |
ITA |
3:33.63 Q NU20R |
| 3 | 2 | 1 | AUS | Australia U20 |
AUS |
3:33.68 Q SB |
| 4 | 2 | 2 | GBR | Great Britain & NI U20 |
GBR |
3:33.82 Q SB |
| 5 | 1 | 3 | GER | Germany U20 |
GER |
3:34.35 Q SB |
| 6 | 3 | 2 | NGR | Nigeria U20 |
NGR |
3:35.28 Q SB |
| 7 | 2 | 3 | SLO | Slovenia U20 |
SLO |
3:35.60 Q NU20R |
| 8 | 3 | 3 | JAM | Jamaica U20 |
JAM |
3:35.93 Q |
| 9 | 4 | 2 | RSA | South Africa U20 |
RSA |
3:36.92 SB |
| 10 | 4 | 3 | POL | Poland U20 |
POL |
3:37.41 SB |
| 11 | 5 | 3 | CZE | Czechia U20 |
CZE |
3:38.07 SB |
| 12 | 5 | 2 | CAN | Canada U20 |
CAN |
3:38.41 SB |
| 13 | 6 | 2 | ESP | Spain U20 |
ESP |
3:38.70 SB |
| 14 | 3 | 1 | IND | India U20 |
IND |
3:39.53 Q |
| 15 | 4 | 1 | SVK | Slovak Republic U20 |
SVK |
3:39.93 NU20R |
| 16 | 7 | 2 | IRL | Ireland U20 |
IRL |
3:40.06 |
| 17 | 6 | 3 | BRA | Brazil U20 |
BRA |
3:40.65 SB |
| 18 | 5 | 1 | BEL | Belgium U20 |
BEL |
3:42.24 |
| 19 | 7 | 3 | ECU | Ecuador U20 |
ECU |
3:43.02 NU20R |
| 20 | 6 | 1 | BAR | Barbados U20 |
BAR |
3:43.20 |
| 21 | 8 | 3 | NZL | New Zealand U20 |
NZL |
3:44.68 SB |
| 22 | 8 | 2 | MEX | Mexico U20 |
MEX |
3:48.07 |
| 1 | BAH | Bahamas U20 |
BAH |
DNS |