# Swimming at the 2024 Summer Olympics – Mixed 4 × 100 metre medley relay

The mixed 4 × 100 metre medley relay event at the 2024 Summer Olympics was held on 2 and 3 August 2024 at Paris La Défense Arena, which was converted to a swimming pool for the swimming events. Since an Olympic size swimming pool is 50 metres long, each swimmer had to swim two lengths of the pool with their respective stroke.

## Records

Prior to this competition, the existing world and Olympic records were as follows.
| World record | Great Britain (GBR) Kathleen Dawson (58.80)Adam Peaty (56.78)James Guy (50.00)Anna Hopkin (52.00) | 3:37.58 | Tokyo, Japan | 31 July 2021 |
| Olympic record | Great Britain (GBR) Kathleen Dawson (58.80)Adam Peaty (56.78)James Guy (50.00)Anna Hopkin (52.00) | 3:37.58 | Tokyo, Japan | 31 July 2021 |
The following record was established during the competition:
| Date | Round | Name | Nationality | Time | Record |
| 3 August | Final | Ryan Murphy (52.08) Nic Fink (58.29) Gretchen Walsh (55.18) Torri Huske (51.88) | United States | 3:37.43 | WR |

## Qualification

For the relays, a maximum of 16 qualifying teams in each event must be permitted to accumulate a total of 112 relay teams; each NOC may enter only one team. The top three teams in each relay race at the 2023 World Aquatics Championships in Fukuoka, Japan will directly book a slot for their corresponding event at the Olympics, while the remaining thirteen vying for qualification per relay race must attain their best time from the heats and finals at the combined 2023 and 2024 meet in Doha.

## Competition format

The competition consists of two rounds: heats and a final. The teams with the best 8 times in the heats advance to the final. Swim-offs are used as necessary to break ties for advancement to the next round (final).

## Schedule

All times are Central European Summer time (UTC+2)
| Date | Time | Round |
| 2 August 2024 | 12:03 | Heats |
| 3 August 2024 | 21.58 | Final |

## Results
### Heats

Results :
| Rank | Heat | Lane | Swimmer | Time | Notes |
| 1 | 2 | 5 | United States Regan Smith (57.87) Charlie Swanson (59.65) Caeleb Dressel (50.10) Abbey Weitzeil (53.36) | 3:40.98 | Q |
| 2 | 1 | 4 | Australia Iona Anderson (58.81) Zac Stubblety-Cook (59.68) Emma McKeon (55.86) Kyle Chalmers (47.07) | 3:41.42 | Q |
| 3 | 2 | 4 | China Xu Jiayu (53.16) Tang Qianting (1:05.44) Zhang Yufei (56.59) Pan Zhanle (47.07) | 3:42.26 | Q |
| 4 | 1 | 5 | Netherlands Kai van Westering [nl] (54.25) Caspar Corbeau (59.28) Tessa Giele (57.81) Marrit Steenbergen (52.26) | 3:43.60 | Q |
| 5 | 2 | 3 | Great Britain Kathleen Dawson (1:00.18) James Wilby (59.35) Joe Litchfield (51.37) Anna Hopkin (52.83) | 3:43.73 | Q |
| 6 | 1 | 3 | Canada Blake Tierney (53.81) Apollo Hess (1:00.46) Maggie Mac Neil (56.14) Taylor Ruck (53.46) | 3:43.87 | Q |
| 7 | 2 | 7 | France Yohann Ndoye-Brouard (52.48) Antoine Viquerat (59.91) Lilou Ressencourt (58.55) Marie Wattel (53.05) | 3:43.99 | Q, NR |
| 8 | 2 | 6 | Japan Riku Matsuyama (54.83) Taku Taniguchi (59.69) Mizuki Hirai (56.52) Rikako Ikee (53.21) | 3:44.25 | Q |
| 9 | 1 | 6 | Germany Ole Braunschweig (54.05) Melvin Imoudu (59.33) Angelina Köhler (56.60) Nina Holt (54.77) | 3:44.75 | |
| 10 | 2 | 8 | Israel Anastasia Gorbenko (59.91) Ron Polonsky (59.56) Gal Cohen Groumi (50.84) Andrea Murez (55.02) | 3:45.33 | |
| 11 | 1 | 7 | Italy Michele Lamberti (54.42) Nicolò Martinenghi (59.02) Costanza Cocconcelli (58.47) Sofia Morini (53.89) | 3:45.80 | |
| 12 | 2 | 2 | Sweden Hanna Rosvall (1:00.17) Erik Persson (59.95) Sara Junevik (57.22) Robin Hanson (48.81) | 3:46.15 | |
| 13 | 2 | 1 | Greece Apostolos Christou (52.83) Evangelos Nthoumas (1:00.34) Anna Ntountounaki (57.85) Theodora Drakou (55.38) | 3:46.40 | |
| 14 | 1 | 2 | Poland Kacper Stokowski (54.10) Dominika Sztandera (1:07.92) Adrian Jaśkiewicz (51.87) Kornelia Fiedkiewicz (54.30) | 3:48.19 | |
| 15 | 1 | 1 | South Korea Lee Eun-ji (1:01.56) Choi Dong-yeol (59.99) Kim Ji-hun (52.70) Hur Yeon-kyung (54.53) | 3:48.78 | |
| 16 | 1 | 8 | Brazil Guilherme Basseto (54.32) Gabrielle Roncatto (1:16.74) Nicolas Albiero (52.27) Stephanie Balduccini (53.94) | 3:57.27 | |

### Final

Results :
| Rank | Lane | Team | Time | Notes |
| | 4 | United States Ryan Murphy (52.08) Nicolas Fink (58.29) Gretchen Walsh (55.18) Torri Huske (51.88) | 3:37.43 | WR |
| | 3 | China Xu Jiayu (52.13) Qin Haiyang (57.82) Zhang Yufei (55.64) Yang Junxuan (51.96) | 3:37.55 | AS |
| | 5 | Australia Kaylee McKeown (57.90) Joshua Yong (58.43) Matthew Temple (50.42) Mollie O'Callaghan (52.01) | 3:38.76 | OC |
| 4 | 1 | France Yohann Ndoye-Brouard (52.80) Leon Marchand (58.66) Marie Wattel (56.44) Beryl Gastaldello (53.06) | 3:40.96 | NR |
| 5 | 7 | Canada Kylie Masse (58.67) Finlay Knox (59.64) Josh Liendo (50.08) Maggie Mac Neil (53.02) | 3:41.41 | |
| 6 | 6 | Netherlands Kira Toussaint (1:00.50) Caspar Corbeau (59.04) Nyls Korstanje (51.19) Marrit Steenbergen (52.39) | 3:43.12 | |
| 7 | 2 | Great Britain Kathleen Dawson (1:00.68) James Wilby (59.00) Duncan Scott (51.61) Anna Hopkin (53.02) | 3:44.31 | |
| 8 | 8 | Japan Riku Matsuyama (55.00) Taku Taniguchi (1:00.48) Mizuki Hirai (56.46) Rikako Ikee (53.23) | 3:45.17 | |