The organisers need about 40 people to help with the cycling and running part of the big race on Sunday 10 July.
This year’s event is the qualifying race for Jersey’s Commonwealth team and around 450 people are expected to take part with at least 100 competing from overseas.
You don’t need to have marshalled before, just free for up to four hours and over 18.
If you can help, you can either download a volunteer form here or get in touch with the organisers via email at info@jersey-triathlon.com or by giving them a call on 505926.