| | Top level | Event type
Shortboard, Women – Semi-Finals
| Date | 27 July 2021 — 13:00 | |
|---|---|---|
| Location | Tsurigasaki Surfing Beach, Torami, Chiba | |
| Format | Winners advance to final round. | |
| Head Judge | Glen Elliott |  AUS |
| Head Judge | Richard Pierce |  USA |
| Judge 1 | Luiz Pereira |  BRA |
| Judge 2 | Dan Kosoof |  NZL |
| Judge 3 | Tory Gilkerson | USA |
| Judge 4 | Benjamin Lowe | AUS |
| Judge 5 | Bruno Truch |  FRA |
| Judge 6 | Masato Kato |  JPN |
| Judge 7 | Nuno Trigo |  POR |
Heat #1
| Time | 13:00 |
|---|
| Pos | Competitor | NOC | Points | Best Wave | Second-Best Wave | Wave 1 | Wave 2 | Wave 3 | Wave 4 | Wave 5 | Wave 6 | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Bianca Buitendag |  RSA | 11.00 | 6.67 | 4.33 | 3.67 | 4.33 | 6.67 | 0.50 | 0.43 | – | ||
| 2 | Caroline Marks | USA | 3.67 | 3.67 | 0.00 | 0.50 | 0.53 | 3.00 | 0.57 | 3.67 | PI | 1 |
Heat #2
| Time | 13:36 |
|---|
| Pos | Competitor | NOC | Points | Best Wave | Second-Best Wave | Wave 1 | Wave 2 | Wave 3 | Wave 4 | Wave 5 | Wave 6 | Wave 7 | Wave 8 | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Carissa Moore | USA | 8.33 | 4.50 | 3.83 | 0.43 | 3.50 | 4.50 | 2.83 | 3.30 | 3.83 | – | – | ||
| 2 | Amuro Tsuzuki | JPN | 7.43 | 4.50 | 2.93 | 0.47 | 2.77 | 2.93 | 4.50 | 0.70 | 0.93 | 0.30 | 0.33 |