Deniz Ertan (born January 1, 2004) is a Turkish swimmer specialized in freestyle swimming. She qualified for the 800m freestyle event of the 2020 Summer Olympics. She is a member of Fenerbahçe Swimming While living in Ankara, Turkey, Ertan attended TED Ankara College. She won the bronze medal in the 200m individual medley event at the 2019 European Youth Summer Olympic Festival in Baku, Azerbaijan. Her collegiate swimming career began in 2022 at Georgia Tech University, swimming under head coach Courtney Shealy Hart.