Tayisiya Morderger (born 7 March 1997) is a German tennis player. Morderger has career-high singles ranking of world No. 400, achieved on 18 September 2017, and a best WTA doubles ranking of No. 242, reached on 3 February 2020. She has won five singles titles and ten doubles titles on tournaments of the ITF Circuit. Morderger made her WTA Tour main-draw debut at the 2020 Prague Open, partnering her twin sister Yana in the doubles event, falling to Lucie Hradecká and Kristýna Plíšková in the first round.