| Event: | Women's 300 metre freestyle |
| Games: | 1920 Summer |
| Venue: | Stade Nautique d'Antwerp |
| Dates: | August 26–28 |
| Competitors: | 16 |
| Nations: | 7 |
| Gold: | Ethelda Bleibtrey |
| Goldnoc: | USA |
| Silver: | Margaret Woodbridge |
| Silvernoc: | USA |
| Bronze: | Frances Schroth |
| Bronzenoc: | USA |
The women's 300 metre freestyle was a swimming event held as part of the swimming at the 1920 Summer Olympics programme.[1] It was the first appearance of the event, which was later adjusted to 400 metres to match the men's competition.
A total of 16 swimmers from seven nations competed in the event, which was held on Thursday, August 26 and on Saturday, August 28, 1920.
These were the standing world and Olympic records (in minutes) prior to the 1920 Summer Olympics.
| World Record | 4:56.2 |  Fanny Durack | ? | 1912 | |
|---|---|---|---|---|---|
| Olympic Record | - | none | - | - |
In the first semi-final Ethelda Bleibtrey set a new world record with 4:41.4 minutes. She bettered her own record in the final with 4:34.0 minutes.
Thursday, August 26, 1920: The fastest two in each semi-final and the fastest third-placed from across the semi-finals advanced.
Semifinal 1
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 4:41.4 | Q WR | ||||
| 2 | 4:57.8 | Q | ||||
| 3 | 5:07.0 | |||||
| 4 | 5:07.2 | |||||
| 5 |
Semifinal 2
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 4:56.6 | Q | ||||
| 2 | 5:04.6 | Q | ||||
| 3 | 5:04.8 | q | ||||
| 4 | ||||||
| 5 |
Semifinal 3
| Place | width=200 | Swimmer | width=90 | Time | width=90 | Qual. |
|---|---|---|---|---|---|---|
| 1 | 5:02.0 | Q | ||||
| 2 | 5:03.2 | Q | ||||
| 3 | 5:29.6 | |||||
| 4 | 5:33.0 | |||||
| 5 | ||||||
| 6 |
Saturday, August 28, 1920:
| Place | width=200 | Swimmer | width=90 | Time |
|---|---|---|---|---|
| 1 | 4:34.0 WR | |||
| 2 | 4:42.8 | |||
| 3 | 4:52.0 | |||
| 4 | 4:52.4 | |||
| 5 | ||||
| 6 | ||||
| 7 |