| Games: | Summer Youth Olympics |
| Games Link: | 2018 Summer Youth Olympics |
| Year: | 2018 |
| Noc: | COK |
| Nocname: | Cook Islands Sports and National Olympic Committee |
| Competitors: | 1 |
| Sports: | 1 [1] |
| Location: | Buenos Aires, Argentina |
| Start Date: | 6 |
| End Date: | 18 October 2018 |
| Gold: | 0 |
| Silver: | 0 |
| Bronze: | 0 |
| Appearances: | auto |
Cook Islands participated at the 2018 Summer Youth Olympics in Buenos Aires, Argentina from 6 October to 18 October 2018.
See main article: Swimming at the 2018 Summer Youth Olympics. The Cook Islands qualified 1 athlete.
| Athlete | Event | Heats | Semifinals | Final | ||||
|---|---|---|---|---|---|---|---|---|
| Time | Rank | Time | Rank | Time | Rank | |||
| align=left rowspan=2 | Bede Aitu | 50 metre backstroke | 28.90 | 24 | did not advance | |||
| 100 metre backstroke | 1:03.49 | 25 | did not advance | |||||