2016: Produce 101 and I.O.I
In 2016, she participated in Mnet's survival television show, Produce 101 as a trainee representing JYP Entertainment. She finished the survival in first place, becoming the center of the girl group I.O.I.
On May 4, 2016, the group debuted with the mini album Chrysalis, and its title track, "Dream Girls".
2017: Unnies, Girls Next Door, solo activities
After the disbandment of I.O.I on January 29, Somi signed an official artist contract with JYP Entertainment, meaning she would be able to pursue solo activities and brand endorsements until her official debut.
Somi then went onto being cast in the reality-drama show, Idol Drama Operation Team in May 2017, as a representative of I.O.I. She played the role of high school student named Bo-ram, and then later became part of a special girl group named Girls Next Door formed by her fellow cast members in July 2017.
2018: New label
On August 20, 2018, it was announced that Somi left JYP Entertainment, and confirmed to have joined YG Entertainment's sub-label The Black Label on September 23, 2018. In late November, it was reported that Somi was working on new music with the goal of making a solo debut in March 2019. It was later scheduled for May 1, then delayed to late May, and finally for June 13.
2019: "Birthday", I.O.I reunion and ITZY's rumor
Finally, on June 13, Somi debuted as a soloist with the digital single album "Birthday". On music shows, she also performed the other track, "Outta My Head".
On July 1, it was announced that I.O.I would make a return under a new agency called Studio Blue. The return would be in October 2019, later delayed to December, with nine members, sadly Somi not being one of them due to her solo activities.
On September 3, pre-debut profile photos of ITZY leaked on the internet, and something caught the eye of netizens. The photos did not include member Yuna, but Somi, which indicates that she was included in the group's line-up, but was replaced by Yuna when she left the company.
- "Birthday" (2019)
- "Flower, Wind and You" (with Huihyeon, Yoojung and Chungha) (2016)
- "You, Who?" (with Eric Nam) (2017)
Music video appearances
- SIXTEEN (Mnet, 2015) - contestant
- Produce 101 (Mnet, 2016) - contestant
- Sister's Slam Dunk, Season 2 (KBS2, 2017)
- Idol Drama Operation Team (KBS2, 2017)
- Produce 48 (Mnet, 2018) - special MC (eps. 1 & 5)
- CJ Alaska Salmon (2016)
- Elite Uniforms (2017)
- Sudden Attack (2017)
- Special Soldier (2017)
- Jambangee jeans (2017)
- American Tourister (2017)
- Fanta (2017-2019)
- Reebok Classic (2017-2018)
- Skoolooks (2017-2018)
- GIVERNY (2018)
- NUOVO (2019)
- BCCard (2019)
- Shiseido Korea (2019)
- Alba Heaven (2019)
- Somi, like her father, is a taekwondo black belt holder. She holds a third-degree black belt, but could not gain the fourth-degree black belt due to her being too young.
- Somi was bullied as a child for being of mixed descent.
- Somi can speak Korean and English fluently.
- She has trained for 1 year and 8 months, including SIXTEEN. If including Produce 101, then she has trained for 2 years.
- During the production of Produce 101, Somi has received the nickname "Vitamin" due to her beagle-like personality.
- She has a younger sister named Evelyn.
- Somi is a fan of Big Bang, 2NE1, BTS, Seventeen and more.
- She is extremely extroverted. Her MBTI personality type is ENFP. 
- ↑ 1.0 1.1 1.2 The Black Label says Jeon So Mi's debut is 'coming soon' with a dreamy teaser image!
- ↑ @somsomi0309's Instagram post (May 20, 2019)
- ↑ SIXTEEN: Episodes 1-11
- ↑ Jeon So Mi leaves JYP Entertainment
- ↑ Jeon So Mi confirms her new contract with YG's The Black Label
- ↑ Jeon Somi To Reportedly Make Solo Debut Next Year
- ↑ Update: The Black Label Announces Date For Jeon Somi’s Debut
- ↑ Soompi: I.O.I Confirmed To Return With 9 Members In October
- ↑ Soompi: I.O.I Confirmed To Be Delaying Comeback To December
- ↑ Jeon Somi Was Indeed Preparing To Debut With ITZY, Pre-Debut Profile Pictures Leaked
- ↑ Allkpop: Knetz Talks About ITZY Profile Pictures Before Debut With Jeon Somi
- ↑ 170310 [Sister's Slam Dunk S2 MBTI Test]