| Event: | Men's 400 metres |
| Games: | 2015 |
| Venue: | CIBC Pan Am and Parapan Am Athletics Stadium |
| Dates: | July 22 – July 23 |
| Competitors: | 16 |
| Nations: | 11 |
| Win Value: | 44.56 |
| Win Label: | Winning time |
| Gold: | Luguelín Santos |
| Goldnoc: | DOM |
| Silver: | Machel Cedenio |
| Silvernoc: | TTO |
| Bronze: | Kyle Clemons |
| Bronzenoc: | USA |
| Prev: | 2011 |
| Next: | 2019 |
The men's 400 metres sprint competition of the athletics events at the 2015 Pan American Games will take place between the 22 and 23 of July at the CIBC Pan Am and Parapan Am Athletics Stadium.[1] The defending Pan American Games champion is Nery Brenes of Costa Rica.
Prior to this competition, the existing world and Pan American Games records were as follows:
| World record | 43.18 | Seville, Spain | August 26, 1999 | ||
| Pan American Games record | 44.52 | Havana, Cuba | 1991 |
See main article: Athletics at the 2015 Pan American Games – Qualification. Each National Olympic Committee (NOC) was able to enter up to two entrants providing they had met the minimum standard (46.07) in the qualifying period (January 1, 2014 to June 28, 2015).[2]
| Date | Time | Round | |
|---|---|---|---|
| July 22, 2015 | 11:00 | Semifinals | |
| July 23, 2015 | 19:20 | Final |
All times shown are in seconds.
| KEY: | bgcolor=ccffcc align=center | q | bgcolor=ccffcc align=center | Q | Qualified | NR | National record | PB | Personal best | SB | Seasonal best | DQ | Disqualified |
| Rank | Heat | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|---|
| 1 | 1 | 45.72 | Q | |||
| 2 | 1 | 45.75 | Q | |||
| 3 | 2 | 45.85 | Q | |||
| 4 | 2 | 46.06 | Q | |||
| 5 | 2 | 46.09 | Q | |||
| 6 | 1 | 46.16 | Q | |||
| 7 | 1 | 46.26 | q | |||
| 8 | 1 | 46.39 | q | |||
| 9 | 2 | 46.43 | ||||
| 10 | 2 | 46.53 | ||||
| 11 | 1 | 46.80 | ||||
| 12 | 2 | 46.81 | ||||
| 13 | 2 | 46.91 | ||||
| 14 | 2 | 47.56 | ||||
| 15 | 1 | 47.61 | ||||
| 16 | 1 | 48.54 |
| Rank | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|
| 44.56 | SB | ||||
| 44.70 | |||||
| 44.84 | PB | ||||
| 4 | 44.85 | SB | |||
| 5 | 45.20 | ||||
| 6 | 45.58 | ||||
| 7 | 46.07 | ||||