American Junior Records are those ratified by USATF. Junior Records are restricted to athletes who do not turn 20 at any time during the calendar year in which the mark is made.
Symbols: + = event not officially recognized by USATF; (A) = altitude-aided mark–over 1000m of altitude (in affected events only); i = made indoors; p = mark still pending ratification
| Track Events | ||||
| 100 | 9.97 | Trayvon Bromell (Baylor) | Eugene, Oregon | 6/13/14 |
| 200 | 20.09 | Noah Lyles (Virginia HS) | Eugene, Oregon | 7/09/16 |
| 400 | 43.87 | Steve Lewis (UCLA) | Seoul, South Korea | 9/28/88 |
| 800 | 1:43.55 | Donavan Brazier (Texas A&M) | Eugene, Oregon | 6/10/16 |
| 1500 | 3:36.1 | Jim Ryun (Kansas) | Berkeley, California | 7/17/66 |
| Mile | 3:51.3 | Jim Ryun (Kansas) | Berkeley, California | 7/17/66 |
| Steeple | 8:33.8 | John Gregorek (Georgetown) | Philadelphia, Pennsylvania | 5/20/79 |
| 3000 | 7:58.0 | Gerry Lindgren (Washington State) | Karlsruhe, Germany | 7/05/65 |
| [7:49.16 Galen Rupp (Oregon) in ’05 never ratified] | ||||
| 5000 | 13:25.46 | German Fernandez (Oklahoma State) | Eugene, Oregon | 6/29/06 |
| 10,000 | 28:32.7 | Rudy Chapa (Indiana HS) | Des Moines, Iowa | 4/24/76 |
| [28:18.52 Galen Rupp (Oregon) in ’05 never ratified] | ||||
| 110 Hurdles | 13.08 | Wayne Davis (North Carolina HS) | Port-of-Spain, Trinidad | 7/31/09 |
| Sr 110H+ | 13.23 | Renaldo Nehemiah (Maryland) | Zürich, Switzerland | 8/16/78 |
| 400 Hurdles | 48.02 | Danny Harris (Iowa State) | Los Angeles, California | 6/17/84 |
| Relay Events | ||||
| 4 x 100 | 38.66 | National Team | Grossetto, Italy | 7/18/04 |
| (David Kimmons, Demi Omole, Ivory Williams, LaShawn Merritt) | ||||
| 4 x 400 | 3:00.33 | National Team | Trujillo, Peru | 7/23/17 |
| (Brian Herron 45.1, Zach Shinnick 45.1, Sean Hooper 44.73, Josephus Lyles 45.36) | ||||
| Field Events | ||||
| High Jump | 2.31 | 7-7 | Andra Manson (Texas HS) | Kingston, Jamaica | 7/18/02 |
| Pole Vault | 5.90 | 19-4¼ | Mondo Duplantis (Louisiana HS) | Austin, Texas | 4/01/17 |
| 5.92 | 19-5p | Mondo Duplantis (Louisiana HS) | Austin, Texas | 3/31/18 | |
| 5.93 | 19-5½p | Mondo Duplantis (Louisiana HS) | Baton Rouge, Louisiana | 5/05/18 | |
| 5.95 | 19-6¼p | Mondo Duplantis (Louisiana HS) | Berlin, Germany | 8/12/18 | |
| 6.00 | 19-8¼p | Mondo Duplantis (Louisiana HS) | Berlin, Germany | 8/12/18 | |
| 6.05 | 19-10¼p | Mondo Duplantis (Louisiana HS) | Berlin, Germany | 8/12/18 | |
| Long Jump | 8.34 | 27-4½ | Randy Williams (USC) | Munich, Germany | 9/08/72 |
| Triple Jump | 17.13 | 56-2½ | Will Claye (Oklahoma) | Fayetteville, Arkansas | 6/13/09 |
| Shot | 22.02 | 72-3 | Jordan Geist (Pennsylvania HS) | Trujillo, Peru | 7/23/17 |
| 22.06 | 72-4½p | Tripp Piperi (Texas) | Tampere, Finland | 7/10/18 | |
| Sr Shot+ | 20.65 | 67-9 | Michael Carter (Texas HS) | Boston, Massachusetts | 7/04/79 |
| Discus | 65.34 | 214-4 | Mason Finley (Colorado HS) | Port-of-Spain, Trinidad | 7/31/09 |
| Sr Discus+ | 63.22 | 207-5 | Brian Milne (Penn State) | University Park, Pennsylvania | 3/28/92 |
| Hammer | 80.79 | 265-0 | Conor McCullough (Princeton) | Moncton, New Brunswick | 7/25/10 |
| Sr Hammer+ | 65.89 | 216-2 | Jake Freeman (Rhode Island HS) | Philadelphia, Pennsylvania | 4/24/99 |
| Javelin | 74.64 | 244-10 | Joe Zimmerman (Washington) | Moncton, New Brunswick | 7/23/10 |
| [77.84 | 255-4 Sam Crouser (Oregon HS) in ’10 never ratified] | ||||
| Multi-Events | ||||
| Decathlon | 8037 | Harrison Williams (Stanford) | Edmonton, Alberta | 7/31–8/01/15 |
| (10.67w, 6.98/22-10¾, 13.71/44-11¾, 2.03/6-8, 48.28 [4182], 14.41, 39.68/130-2, 5.00/16-4¾, 51.77/169-10, 4:29.20 [3855]) | ||||
| Sr Decathlon+ | 7892 | Gunnar Nixon (Arkansas) | Des Moines, Iowa | 6/06–07/12 |
| (10.93w, 23-9½/7.25, 45-½/13.73, 6-8¾/2.05, 48.92 [4177], 14.51, 119-8/36.48, 15-1/4.60, 184-1/56.12, 4:30.41 [3715]) | ||||
| Road Event | ||||
| Marathon+ | 2:15:28 | Paul Gompers (Harvard) | Huntsville, Alabama | 12/10/83 |
| Walk Events | ||||
| 5000 | 20:06.0 | Trevor Barron (South Park TC) | San Diego, California | 6/13/10 |
| 5K(r) | 21:05 | Trevor Barron (New York AC) | Eugene, Oregon | 6/26/11 |
| 10,000 | 41:23.14 | Tyler Sorenson (California HS) | Villeneuve-d’Ascq, France | 7/09/11 |
| 10K(r) | 41:35 | Trevor Barron (New York AC) | Eugene, Oregon | 6/26/11 |
| 20,000 | 1:23:49.4 | Trevor Barron (South Park TC) | Tusula, Finland | 9/04/10 |
| 20K(r) | 1:23:26 | Trevor Barron (New York AC) | Eugene, Oregon | 6/26/11 |
as of August 20, 2018