Lee Jieun, better known by her stage name IU, is of the most successful solo artists in K-pop history.
- Languages spoke: Korean, English, Chinese, Japanese
- Training period: 2007-2008
- Star sign: Taurus
- Schooling: Dongduk Women’s High School
- After IU’s contract with Kakao M expired, she agreed to renew the contract but with one condition, that is to keep the IU team by her side and increase their salaries all together
- When IU was part of Good Entertainment she was supposed to debut as "5 girls" together with G.NA, After School's Uee, Wonder Girl's Yubin, 4minute's Gayoon and Secret's Hyosung
- Her company gave her name, IU which has the meaning ‘You’ and ‘I’ will become one through music.
- IU is best friends with Suzy, Jiyeon and actress Yoon In Na
- IU said that in the past she struggled with bulimia
- IU failed an audition at JYP but got into Leon Entertainment. Later JYP said that he was going to fire whoever let IU go
- IU's family suffered from financial difficulties so she would stay with her brother, cousin, and grandmother in one home. However that home was infested with cockroaches
- IU has been nominated for more than 100 awards, winning over fifty of them
- In 2012 IU was identified as one of the most influential people in South Korea by Forbes Korea Power Celebrity list, since then she has been mentioned five more times
- in 2015 and later in 2018 IU has made two seperate donations of ₩100,000,000 (roughly $90,000 USD) to the Green Umbrella Children's Fund
- IU established a scholarship at her high school alma-mater in 2016 and regularly donates there. The scholarship is dubbed the "IU Scholarship" designed to help graduates from underdeveloped families.
- In 2018 IU provided ₩20,000,000 ($18,000 USD) in financial aid to five college students, helping cover their room and board
- IU is an ambassador for South Korea's National Police Agency in their anti-bullying campaigns. She was made an honorary member of the police force in 2013
- Starcraft 2's Void ray is nicknamed the IU ray because during its charge up is in sync with IU's 3 high notes in "Good Day"