Ekaterina Andreevna Bychkova is a Russian tennis player. Bychkova has won nine singles and four doubles titles on the ITF tour in her career. On 20 February 2006, she reached her best singles ranking of world number 66. On 29 January 2007, she peaked at world number 106 in the doubles rankings. Bychkova is famous for defeating defending champion Svetlana Kuznetsova in the first round of the 2005 US Open. It was the first time a defending US Open champion had lost in the first round.