Frederik Søgaard Mortensen (born 25 July 1997) is a Danish badminton player. He was the silver medalist in the boys' doubles at the 2015 World Junior Championships and in the mixed doubles at the 2015 European Junior Championships and also won bronzes in the boys' doubles and the team events at the European Junior Championships. Søgaard was part of the Denmark winning team at the 2019, 2021 European Mixed Team and the 2020 European Men's Team Championships.