Medi Eira Harris (born 15 September 2002) is a Welsh international swimmer competing for Great Britain and Wales in backstroke and freestyle.

She was part of the gold medal-winning women's 4x100 freestyle relay team at the 2022 European Aquatics Championships.

Representing Wales at the 2022 Commonwealth Games, she won a bronze medal in the women's 100 metre backstroke.

In 2023, she won the gold medal at the 2023 British Swimming Championships in the 100 metres backstroke.

[6] After finishing third in the 200 metres freestyle at the 2024 Aquatics GB Swimming Championships, Harris qualified for the relay team for the 2024 Summer Olympics.