| POS | Rank | Heat | BIB | ATHLETE | COUNTRY | RESULTS | ms* | WIND | 
|---|---|---|---|---|---|---|---|---|
| 1 | 1 | 1 | 2350 | Zharnel HUGHES |  GBR | 19.99 Q | 0.0 | |
| 2 | 1 | 7 | 2969 | Kenneth BEDNAREK |  USA | 20.01 Q | -0.1 | |
| 3 | 1 | 2 | 3007 | Noah LYLES |  USA | 20.05 Q | -0.1 | |
| 4 | 2 | 1 | 2138 | Aaron BROWN |  CAN | 20.08 Q | 0.0 | |
| 5 | 2 | 7 | 2221 | Alexander OGANDO |  DOM | 20.14 Q | .132 | -0.1 | 
| 6 | 1 | 4 | 2155 | Brendon RODNEY |  CAN | 20.14 Q SB | .133 | -0.2 | 
| 7 | 3 | 1 | 2821 | Luxolo ADAMS |  RSA | 20.15 Q SB | 0.0 | |
| 8 | 1 | 6 | 3003 | Erriyon KNIGHTON |  USA | 20.17 Q | -0.5 | |
| 9 | 1 | 3 | 2102 | Letsile TEBOGO |  BOT | 20.22 Q | -1.4 | |
| 10 | 2 | 2 | 2545 | Andrew HUDSON |  JAM | 20.25 Q | -0.1 | |
| 11 | 4 | 1 | 2568 | Shota IIZUKA |  JPN | 20.27 q SB | 0.0 | |
| 12 | 2 | 6 | 2140 | Andre DE GRASSE |  CAN | 20.28 Q | -0.5 | |
| 13 | 5 | 1 | 2701 | Taymir BURNET |  NED | 20.31 q PB | 0.0 | |
| 14 | 3 | 6 | 2824 | Sinesipho DAMBILE |  RSA | 20.34 Q | .333 | -0.5 | 
| 15 | 1 | 5 | 2598 | Towa UZAWA |  JPN | 20.34 Q | .336 | -0.2 | 
| 16 | 2 | 5 | 3006 | Courtney LINDSEY |  USA | 20.39 Q | -0.2 | |
| 17 | 3 | 2 | 2208 | Ondřej MACÍK |  CZE | 20.40 Q | .393 | -0.1 | 
| 18 | 3 | 5 | 2539 | Rasheed DWYER |  JAM | 20.40 Q | .394 | -0.2 | 
| 19 | 2 | 3 | 2644 | Joseph FAHNBULLEH |  LBR | 20.42 Q | -1.4 | |
| 20 | 4 | 5 | 2948 | Tarsis Gracious OROGOT |  UGA | 20.44 q | .431 | -0.2 | 
| 21 | 2 | 4 | 2109 | Renan CORREA |  BRA | 20.44 Q | .440 | -0.2 | 
| 22 | 4 | 6 | 2521 | Filippo TORTU |  ITA | 20.46 | -0.5 | |
| 23 | 6 | 1 | 2496 | Eseosa Fostine DESALU |  ITA | 20.49 SB | 0.0 | |
| 24 | 3 | 3 | 2880 | William REAIS |  SUI | 20.50 Q | -1.4 | |
| 25 | 4 | 3 | 2373 | Joshua HARTMANN |  GER | 20.51 | -1.4 | |
| 26 | 3 | 7 | 2715 | Alaba Olukunle AKINTOLA |  NGR | 20.54 Q | -0.1 | |
| 27 | 5 | 6 | 2398 | Joseph Paul AMOAH |  GHA | 20.56 | .551 | -0.5 | 
| 28 | 3 | 4 | 2829 | Shaun MASWANGANYI |  RSA | 20.56 Q | .557 | -0.2 | 
| 29 | 4 | 7 | 2755 | Alonso EDWARD |  PAN | 20.63 | -0.1 | |
| 30 | 4 | 2 | 3051 | Tapiwanashe MAKARAWU |  ZIM | 20.64 | -0.1 | |
| 31 | 4 | 4 | 2597 | Koki UEYAMA |  JPN | 20.66 | -0.2 | |
| 32 | 5 | 2 | 2886 | Ján VOLKO |  SVK | 20.69 | -0.1 | |
| 33 | 5 | 3 | 2482 | Blessing Akwasi AFRIFAH |  ISR | 20.73 | -1.4 | |
| 34 | 6 | 2 | 2126 | Jorge VIDES |  BRA | 20.80 | -0.1 | |
| 35 | 5 | 5 | 2912 | Chun-Han YANG |  TPE | 20.82 | -0.2 | |
| 36 | 5 | 7 | 2124 | Lucas RODRIGUES DA SILVA |  BRA | 20.86 | -0.1 | |
| 37 | 6 | 6 | 2904 | Sibusiso MATSENJWA |  SWZ | 20.88 | -0.5 | |
| 38 | 6 | 5 | 2931 | Ramil GULIYEV |  TUR | 20.89 | -0.2 | |
| 39 | 7 | 1 | 2652 | Gediminas TRUSKAUSKAS |  LTU | 20.90 | .893 | 0.0 | 
| 40 | 5 | 4 | 2850 | Nadale BUNTIN |  SKN | 20.90 | .894 | -0.2 | 
| 40 | 5 | 4 | 2448 | Zoltán WAHL |  HUN | 20.90 PB | .894 | -0.2 | 
| 42 | 6 | 3 | 2052 | Aidan MURPHY |  AUS | 20.90 | .895 | -1.4 | 
| 43 | 6 | 7 | 2479 | Taha Hussein YASEEN |  IRQ | 21.01 | -0.1 | |
| 44 | 7 | 6 | 2336 | Guy MAGANGA GORRA |  GAB | 21.04 | -0.5 | |
| 45 | 7 | 3 | 2013 | Marcos SANTOS |  ANG | 21.05 NR | -1.4 | |
| 46 | 7 | 2 | 2634 | Seunghwan KO |  KOR | 21.09 | -0.1 | |
| 47 | 7 | 7 | 2775 | Albert KOMAŃSKI |  POL | 21.16 | -0.1 | |
| 48 | 8 | 2 | 2764 | Leroy KAMAU |  PNG | 21.18 SB | -0.1 | |
| 49 | 7 | 5 | 2360 | Mindia ENDELADZE |  GEO | 21.20 | -0.2 | |
| 50 | 8 | 3 | 2187 | Hachim MAAROUFOU |  COM | 21.29 | -1.4 | |
| 51 | 7 | 4 | 2753 | Mohamed Obaid ALSADI |  OMA | 21.39 | -0.2 | |
| 52 | 8 | 1 | 2002 | Franko BURRAJ |  ALB | 21.52 | 0.0 | |
| 53 | 8 | 6 | 2694 | Yeykell Eliu ROMERO |  NCA | 21.71 | -0.5 | |
| 54 | 9 | 2 | 2403 | Jessy FRANCO |  GIB | 22.04 SB | -0.1 | |
| 4 | 2401 | James DADZIE |  GHA | DNF | ||||
| 7 | 2333 | Ryan ZEZE |  FRA | DQ | ||||
| 5 | 2180 | Emmanuel ESEME |  CMR | DNS | 
ms - Milliseconds - shown when two or more competitors finish with the same time down to hundredths of a second