| Event: | Athletics – Girls' 400 metres |
| Games: | 2014 Summer Youth |
| Venue: | Nanjing Olympic Sports Centre |
| Date: | August 20–23 |
| Competitors: | 21 |
| Nations: | 21 |
| Gold: | Jessica Thornton |
| Goldnoc: | AUS |
| Silver: | Salwa Naser |
| Silvernoc: | BRN |
| Bronze: | Meleni Rodney |
| Bronzenoc: | GRN |
| Prev: | 2010 |
| Next: | 2018 |
The girls’ 400 m competition at the 2014 Summer Youth Olympics was held on 20–23 August 2014 in Nanjing Olympic Sports Center.
| Date | Time | Round | |
|---|---|---|---|
| 20 August 2014 | 20:15 | Heats | |
| 23 August 2014 | 20:35 | Final |
Eight fastest athletes advanced to Final A, the others advanced to Final B, or C according to their times.
| Rank | Heat | Lane | Athlete | Result | Notes | Q | |
|---|---|---|---|---|---|---|---|
| 1 | 1 | 6 | 52.78 | PB | FA | ||
| 2 | 1 | 5 | 53.95 | PB | FA | ||
| 2 | 3 | 6 | 53.95 | PB | FA | ||
| 4 | 3 | 5 | 54.11 | FA | |||
| 5 | 1 | 4 | 54.18 | FA | |||
| 6 | 2 | 4 | 54.24 | PB | FA | ||
| 7 | 1 | 8 | 54.26 | FA | |||
| 8 | 3 | 2 | 54.42 | FA | |||
| 9 | 2 | 6 | 54.54 | FB | |||
| 10 | 2 | 7 | 54.97 | FB | |||
| 11 | 2 | 5 | 55.74 | FB | |||
| 12 | 3 | 8 | 56.22 | PB | FB | ||
| 13 | 1 | 3 | 56.30 | PB | FB | ||
| 14 | 2 | 8 | 56.63 | FB | |||
| 15 | 3 | 7 | 57.23 | FB | |||
| 16 | 3 | 4 | 58.74 | FC | |||
| 17 | 2 | 2 | 58.85 | PB | FC | ||
| 18 | 2 | 3 | 1:00.60 | PB | FC | ||
| 19 | 1 | 2 | 1:04.48 | FC | |||
| 20 | 1 | 7 | 1:04.88 | PB | FC | ||
| 3 | 3 | FC |
| Rank | Final Placing | Lane | Athlete | Result | Notes | |
|---|---|---|---|---|---|---|
| 1 | 4 | 52.50 | PB | |||
| 2 | 5 | 52.74 | PB | |||
| 3 | 6 | 53.33 | PB | |||
| 4 | 4 | 2 | 53.54 | PB | ||
| 5 | 5 | 8 | 53.70 | PB | ||
| 6 | 6 | 7 | 53.82 | |||
| 7 | 7 | 9 | 54.43 | |||
| 8 | 8 | 3 | 54.93 |
| Rank | Final Placing | Lane | Athlete | Result | Notes | |
|---|---|---|---|---|---|---|
| 1 | 9 | 5 | 54.48 | |||
| 2 | 10 | 4 | 54.54 | |||
| 3 | 11 | 8 | 54.92 | |||
| 4 | 12 | 7 | 55.32 | PB | ||
| 5 | 13 | 9 | 55.43 | PB | ||
| 6 | 14 | 6 | 55.52 | |||
| 7 | 15 | 3 | 55.90 |
| Rank | Final Placing | Lane | Athlete | Result | Notes | |
|---|---|---|---|---|---|---|
| 1 | 16 | 4 | 57.91 | PB | ||
| 2 | 17 | 5 | 58.74 | PB | ||
| 3 | 18 | 6 | 1:00.96 | |||
| 4 | 19 | 7 | 1:01.72 | |||
| 5 | 20 | 8 | 1:03.98 | PB | ||
| 3 |