Sejeong (세정) is a South Korean singer and actress under Jellyfish Entertainment. She is a member of the girl group gugudan, its sub-unit SEMINA, and a former member of I.O.I.


2012: K-Pop Star 2

In 2012, Sejeong participated in the second season of competition show K-Pop Star 2, at the age of 16, she was eliminated in the second round, ranking audition, but was later brought back to the show as a wild card by the CEO of YG Entertainment, Yang Hyun Suk. She was ultimately eliminated in the final casting round.[1][2]

2016: Produce 101, I.O.I, gugudan, solo career

In 2016, Sejeong was a contestant on the survival show Produce 101. She ranked 2nd place in the program, thus making her a member of the girl group I.O.I. She was a member of the group until their disbandment on January 29, 2017. She was absent from I.O.I's first single "Whatta Man" promotion's due to her promoting gugudan's debut mini album.

On June 28, 2016, she debuted as a member of gugudan with the group's first mini-album Act.1 The Little Mermaid.

In November 23, 2016, Sejeong participated in Jellyfish's music channel project Jelly Box and released her first single "Flower Way". The single was very successful and topped a lot of major music charts. On November 30, she received her first music award as a solo artist in the show Show Champion.[3][4]

2017–present: Solo career, gugudan SEMINA

On January 2017, she officially became a permanent MC for OnStyle's Get It Beauty. In July 2017, she made her acting debut as the lead, Ra Eun-ho, in KBS2's teen drama "School 2017".[5][6]

In July 2018, she debuted in gugudan's second sub-unit gugudan SEMINA with the trio's first single "Semina".

On March 3, 2020, Jellyfish released teasers for her first mini album Plant, which was released on March 17.

Personal life


She is currently attending Hanyang Women's University.[citation needed]


Mini albums

Digital singles



  • "Legend of the Blue Sea OST Part.10" ("If Only") (2017)
  • "Mr. Sunshine OST Part.13" ("Paramour") (2018)
  • "Crash Landing on You Part.8" ("All of My Days") (2020)


Reality shows


  • School 2017 (KBS2, 2017)

Variety shows

  • Get It Beauty (OnStyle, 2017) - MC
  • Busted! (Netflix, 2018–2019)


  • She represents the number 3 within her group, gugudan.
  • During the course of Produce 101, she got the nickname "God Sejong" because she remained in first and second places and never going lower than that.
  • She trained for 1 year and 7 months until December 2015 when she participated in Produce 101. If including Produce 101, it would been 1 years and 11 months.
  • She was a part of the all-female non-professional soccer club called 'FC Rumor W', along with other idols, such as her fellow member Nayoung, Hayoung of Apink, Jeonghwa of EXID, Mina and Jihyo of TWICE and U.Ji (former of BESTie), and also non-celebrities.[7] On August 11, 2020, it was announced by Hayoung that she and other idols, including Sejeong, decided to leave the team after the controversy surrounding it became too big.[8]



Community content is available under CC-BY-SA unless otherwise noted.