Lea Boy (born 24 January 2000) is a German open water swimmer.
In 2018, she finished in 12th place in the women's 5 km at the 2018 European Aquatics Championships.
She participated at the 2019 World Aquatics Championships, winning a medal.
In 2019, she represented the Germany at the 2019 World Aquatics Championships in Gwangju, South Korea. She competed in the women's 25 km event and she finished in 12th place.