Competitors for 2018 Marathon Swimming World Series
| Athlete | Country | Sports | Date of birth |
|---|---|---|---|
| Leonie Beck |  GER |
OWS/SWI | 27 May 1997 |
| Jack Burnell |  GBR |
OWS/SWI | 13 June 1993 |
| Ana Marcela Cunha |  BRA |
OWS/SWI | 23 March 1992 |
| Rob Muffels | GER |
OWS/SWI | 8 December 1994 |
| Gregorio Paltrinieri |  ITA |
OWS/SWI | 5 September 1994 |
| Xin Xin |  CHN |
OWS | 6 November 1996 |