Yuliya Andreyevna Yefimova (also romanized Efimova, (born April 3, 1992) is a Russian competitive swimmer from Taganrog.
Efimova competed for Russia at the 2008 Beijing Olympics and the 2012 London Olympics. In London she won the bronze medal in the 200 metres breaststroke.
Yefimova beat the long course 50 m breaststroke world record at the Barcelona 2013 FINA World Championships, as well as winning the gold medal in the 50 m and 200 m breaststroke races at the same Championships. She held the world records in short course 50 m and 200 m breaststroke.