Gao Jun was born in Baoding, Hebei province of China. She now resides in Southern California. She is the owner of Gao Jun Table Tennis club in El Monte, CA.
She won a silver medal at the 1992 Summer Olympics in the women's double event, with Chen Zihe for  the Chinese National Team. She moved to the U.S. in 1994 and became a U.S. citizen. She competed for the United States in three consecutive Olympic Games from 2000 to 2008. In 2009, Gao was inducted into the USATT Hall of Fame.
Gao is a nine-time U.S. women's champion. She also has won eleven U.S. national titles in women's doubles and eight titles in mixed doubles with various partners. She was ranked number 1 in the U.S. prior to the 2012 London Olympics but pulled out of the North American Olympic trials due to an injury.