| POS | Rank | Heat | BIB | ATHLETE | COUNTRY | RESULTS |
|---|---|---|---|---|---|---|
| 1 | 1 | 2 | JPN | Japan U20 |
JPN |
39.23 Q WJL |
| 2 | 2 | 2 | USA | United States U20 |
USA |
39.43 Q SB |
| 3 | 3 | 2 | NGR | Nigeria U20 |
NGR |
39.67 q SB |
| 4 | 1 | 1 | CHN | PR of China U20 |
CHN |
39.75 Q SB |
| 5 | 1 | 3 | JAM | Jamaica U20 |
JAM |
39.86 Q |
| 6 | 4 | 2 | AUS | Australia U20 |
AUS |
40.18 q SB |
| 7 | 2 | 1 | THA | Thailand U20 |
THA |
40.24 Q |
| 8 | 2 | 3 | TTO | Trinidad and Tobago U20 |
TTO |
40.32 Q |
| 9 | 3 | 3 | BAH | Bahamas U20 |
BAH |
40.45 |
| 10 | 3 | 1 | BOT | Botswana U20 |
BOT |
40.53 SB |
| 11 | 4 | 3 | NOR | Norway U20 |
NOR |
40.62 NJR |
| 12 | 5 | 3 | RSA | South Africa U20 |
RSA |
40.64 SB |
| 13 | 4 | 1 | POL | Poland U20 |
POL |
40.68 |
| 14 | 5 | 1 | TUR | Turkey U20 |
TUR |
41.18 SB |
| 15 | 5 | 2 | BAR | Barbados U20 |
BAR |
41.39 SB |
| 2 | CAN | Canada U20 |
CAN |
DQ R170.7 | ||
| 3 | ITA | Italy U20 |
ITA |
DQ R170.7 | ||
| 1 | GBR | Great Britain & NI U20 |
GBR |
DNF | ||
| 3 | ZIM | Zimbabwe U20 |
ZIM |
DNS |