Lee Jeong-yun is a South Korean judoka. In 2017, she won one of the bronze medals in the women's 78 kg event at the 2017 Asian Judo Championships held in Hong Kong. In that same year, she also won the silver medal in her event at the 2017 Summer Universiade held in Taipei, Taiwan. At the 2019 Asian-Pacific Judo Championships held in Fujairah, United Arab Emirates, she won one of the bronze medals in the women's 78 kg event. In 2021, she won one of the bronze medals in her event at the 2021 Judo Grand Slam Tashkent held in Tashkent, Uzbekistan.