Lee Hyo-jung(born 13 January 1981 in Seoul) is a female badminton player from South Korea.
She won the gold medal in badminton mixed doubles at the 2008 Beijing Summer Olympics with her partner, Lee Yong-dae. Lee Hyo-jung and Lee Yong-dae were unseeded and in the finals they beat the top seeds and 2005 and 2007 world champions Lilyana Natsir and Nova Widianto of Indonesia, 21-11 , 21-17.
Lee Hyo-jung also won the silver medal in badminton women's doubles at the 2008 Beijing Summer Olympics with her partner, Lee Kyung-won; they were seeded fourth and lost to the second-seeded Chinese pair, Du Jing and Yu Yang.
In May, Lee competed in the 2010 Uber Cup as a member of the South Korean women's national team. There she led her team to its first Uber Cup trophy, winning all 4 doubles matches she competed in through the tourney. In finals, she and her partner Kim Min-Jung won against WR #1 Ma Jin and Wang Xiaoli, beating them 18-21, 21-12, 21-15. Although Lee and Kim were not regular partners and Lee Hyo-Jung stopped playing WD regularly in international games, Lee played exceptionally well, proving why she is the most successful player in 2008 Olympic winning both gold and silver medals.
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In June, Lee continued on playing doubles with Kim Min-Jung, winning Indonesia Open and also finishing as a runner up in Singapore Open. While waiting for Lee Yong Dae to recover from his injury, she has been playing mixed double with Shin Baek-Cheol, although it hasn't been as successful as with Lee Yong-Dae. It is expected that Lee Yong-Dae would recover around August, and they would resume their mixed double partnership in World Championship in Paris.