Yi So-yeon (born June 2, 1978) is a South Korean astronaut and biotechnologist who became the first South Korean citizen to fly in space.

Lee was born and raised in Gwangju, South Korea and graduated from KAIST with a Master’s degree in Mechanical Engineering. In 2006, she was selected as one of two finalists in the Korean Astronaut Program: a mission to send the first Koreans to space. A year later, it was announced that she was to be the backup. However, on March 10, 2008, it was announced that she would be the primary. On April 8, 2008, she was launched into space alongside two Russian cosmonauts. She spent around eleven days in space; on April 19, she returned to the surface.