| Final 21:15 | Team | time | L | | React. | bib | | 1. Lashinda Demus | USA | 52.47s | 3 | WL | 0.149 | 934 | | 2. Melaine Walker | JAM | 52.73s | 8 | SB | 0.219 | 528 | | 3. Natalya Antyukh | RUS | 53.85s | 5 | | 0.151 | 745 | | 4. Kaliese Spencer | JAM | 54.01s | 2 | | 0.195 | 525 | | 5. Anastasiya Rabchenyuk | UKR | 54.18s | 1 | SB | 0.174 | 893 | | 6. Vania Stambolova | BUL | 54.23s | 6 | | 0.260 | 191 | | 7. Zuzana Hejnova | CZE | 54.23s | 4 | | 0.158 | 294 | | 8. Elena Churakova | RUS | 55.17s | 7 | | 0.173 | 750 |
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| Semi-Finals - Tuesday 30.08 - First 2 and Best 2 progress. |
| 1. David Greene | GBR | 48.62s | 5 | | 0.147 | 2. | 441 | | 2. Felix Sanchez | DOM | 49.01s | 4 | | 0.199 | 6. | 306 | | 3. Jehue Gordon | TRI | 49.08s | 3 | | 0.167 | 9. | 1010 | | 4. Isa Phillips | JAM | 49.16s | 6 | | 0.269 | 10. | 599 | | 5. Andres Silva | URU | 49.63s | 7 | | 0.200 | 16. | 1058 | | 6. Emir Bekric | SRB | 49.94s | 1 | | 0.160 | 19. | 954 | | 7. Mahau Suguimati | BRA | 50.89s | 2 | | 0.174 | 23. | 203 | | 8. Kerron Clement | USA | 52.11s | 8 | | 0.162 | 24. | 1070 |
| 1. Javier Culson | PUR | 48.52s | 4 | | 0.203 | 1. | 865 | | 1. Bershawn Jackson | USA | 48.80s | 4 | | 0.174 | 3. | 1087 | | 2. Cornel Fredericks | RSA | 48.83s | 3 | | 0.143 | 4. | 882 | | 3. Angelo Taylor | USA | 48.86s | 6 | | 0.171 | 5. | 1126 | | 2. Luis Jacobus van Zyl | RSA | 49.05s | 6 | | 0.193 | 7. | 900 | | 3. Aleksandr Derevyagin | RUS | 49.07s | 7 | SB | 0.172 | 8. | 906 | | 4. Leford Green | JAM | 49.29s | 8 | | 0.208 | 11. | 595 | | 4. Jeshua Anderson | USA | 49.33s | 5 | | 0.172 | 12. | 1059 | | 5. Georg Fleischhauer | GER | 49.36s | 3 | | 0.144 | 13. | 479 | | 6. Nathan Woodward | GBR | 49.57s | 5 | | 0.150 | 14. | 465 | | 5. Jack Green | GBR | 49.62s | 2 | | 0.199 | 15. | 440 | | 7. Vincent Kiplangat Kosgei | KEN | 49.71s | 2 | | 0.176 | 17. | 657 | | 6. Stanislav Melnykov | UKR | 49.74s | 8 | | 0.183 | 18. | 1051 | | 7. Takayuki Kishimoto | JPN | 50.05s | 1 | | 0.148 | 20. | 621 | | 8. Omar Cisneros | CUB | 50.10s | 1 | | 0.189 | 21. | 277 | | 8. Josef Robertson | JAM | 50.39s | 7 | | 0.156 | 22. | 603 |
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| Heats - Monday 29.08 - First 4 and Best 4 progress. |
| Heat 1. 12:20 | Team | time | L | | React. | | bib | | 1. Kaliese Spencer | JAM | 54.93s | 3 | | 0.162 | 3. | 525 | | 2. Anastasiya Rabchenyuk | UKR | 55.08s | 6 | | 0.208 | 5. | 893 | | 3. Queen Harrison | USA | 55.11s | 5 | | 0.167 | 6. | 947 | | 4. Lauren Boden | AUS | 55.78s | 7 | SB | 0.219 | 12. | 109 | | 5. Vera Barbosa | POR | 56.31s | 2 | | 0.298 | 21. | 717 | | 6. Christine Merrill | SRI | 57.05s | 4 | | 0.203 | 27. | 810 | | 7. Bimbo Miel Ayedou | BEN | 58.80s | 1 | | 0.233 | 34. | 141 |
| Heat 2. 12:28 | Team | time | L | | React. | | bib | | 1. Zuzana Hejnova | CZE | 55.12s | 6 | | 0.196 | 7. | 294 | | 2. Elena Churakova | RUS | 55.39s | 7 | | 0.205 | 9. | 750 | | 3. Elodie Ouedraogo | BEL | 55.40s | 2 | PB | 0.191 | 10. | 139 | | 3. Hanna Titimets | UKR | 55.40s | 4 | | 0.317 | 10. | 905 | | 5. Sara Petersen | DEN | 56.32s | 1 | | 0.161 | 22. | 305 | | 6. Nikolina Horvat | CRO | 56.60s | 5 | | 0.211 | 23. | 270 | | 7. Hanitrasoa Olga Razanamalala | MAD | 57.25s | 3 | PB | 0.190 | 30. | 640 |
| Heat 3. 12:36 | Team | time | L | | React. | | bib | | 1. Lashinda Demus | USA | 54.93s | 4 | | 0.166 | 3. | 934 | | 2. Perri Shakes-Drayton | GBR | 55.90s | 6 | | 0.243 | 13. | 409 | | 3. Hanna Yaroshchuk | UKR | 55.99s | 1 | | 0.193 | 15. | 909 | | 4. Nickiesha Wilson | JAM | 56.08s | 2 | | 0.249 | 16. | 533 | | 5. Jailma de Lima | BRA | 57.21s | 5 | | 0.207 | 28. | 168 | | 6. Birsen Engin | TUR | 57.22s | 7 | | 0.341 | 29. | 869 | | 7. Sharolyn Scott | CRC | 58.78s | 8 | | 0.214 | 33. | 269 | | 8. Fatima Sulaiman Dahman | YEM | 1:11.49 | 3 | PB | 0.189 | 38. | 1001 |
| Heat 4. 12:44 | Team | time | L | | React. | | bib | | 1. Vania Stambolova | BUL | 55.29s | 4 | | 0.259 | 8. | 191 | | 2. Ristananna Tracey | JAM | 55.96s | 6 | | 0.357 | 14. | 527 | | 3. Eilidh Child | GBR | 56.18s | 1 | | 0.156 | 18. | 382 | | 4. Muizat Ajoke Odumosu | NGR | 56.23s | 8 | SB | 0.255 | 19. | 678 | | 5. Nagihan Karadere | TUR | 56.76s | 2 | | 0.277 | 26. | 860 | | 6. Stine Meland Tomb | NOR | 57.51s | 3 | | 0.180 | 31. | 691 | | 7. Deborah Rodriguez | URU | 59.52s | 5 | | 0.199 | 35. | 914 | | 8. Jessica Aguilera | NCA | 1:02.78 | 7 | NR | 0.227 | 37. | 663 |
| Heat 5. 12:52 | Team | time | L | | React. | | bib | | 1. Melaine Walker | JAM | 54.86s | 7 | | 0.339 | 1. | 528 | | 2. Natalya Antyukh | RUS | 54.88s | 8 | | 0.235 | 2. | 745 | | 3. Wenda Theron | RSA | 56.13s | 3 | PB | 0.193 | 17. | 741 | | 4. Jasmine Chaney | USA | 56.28s | 5 | | 0.221 | 20. | 926 | | 5. Satomi Kubokura | JPN | 56.66s | 1 | | 0.168 | 24. | 545 | | 6. Manuela Gentili | ITA | 56.71s | 2 | | 0.192 | 25. | 498 | | 7. Amailya Sharoyan | ARM | 58.54s | 4 | NR | 0.199 | 32. | 106 | | 8. Kyeong-Mi Son | KOR | 1:00.21 | 6 | | 0.222 | 36. | 618 |
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