The 20-year-old is working with the extreme sports team and his role includes maintaining the mountain bikes, fixing and cleaning them as necessary.
Harvey, a Scout leader at 8th Worthing, is representing the UK and helping Scouts from all over the world to make the most of this opportunity of a lifetime over the two-week jamboree.
Harvey said: "My role is to make sure Scouts from around the world gain memorable experiences of mountain biking. I've brushed up on my bike maintenance so I can also teach the young people these important maintenance skills."
The international service team is a multi-national team of 6,000 adults, including nearly 1,000 from the UK, whose job is to 'make the jamboree happen' and make every day a little easier for everyone.
Bear Grylls, chief Scout in the UK, said: "World Scout Jamborees happen only every four years and tens of thousands of Scouts attend each one. They are incredible festivals of peace, friendship and adventure.
"Young people will make friends for life with people from over 150 countries, experience different food, language and culture while learning new skills. It will be the journey of a lifetime."
The 2019 jamboree is jointly hosted by the USA, Canada and Mexico and the theme Unlock a New World focuses on how to create a sustainable world together.