Hyomin’s path to stardom started early when she won the MiMi Princess modeling contest at the age of 8. She was a famous internet ulzzang and even modeled for online shopping malls before debuting with T-ara. She was a trainee under JYP Entertainment and was considered to be a replacement for Hyuna, who was a member of the Wonder Girls in 2007. Before being cast by Core Contents Media, she started appearing in music videos like SS501's "Unlock", SG Wannabe's "Smooth Break-Up", and FT Island's "Heaven".
She was chosen by Core Contents Media to be featured in some of her labelmates' songs prior to her debut. This included Hwang Jung-eum, the Colour Pink project with Seeya, Davichi and Black Pearl. She has also performed on a music show with SeeYa during their promotions for the song, "Hot Girl".
In 2010, Hyomin was in the Wonder Women project group with label mates Seeya and Davichi, along with fellow member Eunjung. She was featured on the soundtrack for SBS's drama Coffee House in 2010 and also collaborated with Brave Brothers for their digital single "Beautiful Girl" in 2011.
On June 14, 2011, Core Contents Media announced that Hyomin would take over leadership as T-ara's third leader for their comeback album, John Travolta Wannabe, and Japanese promotions. She later passed on her leadership to fellow member, Soyeon.
It was revealed that Hyomin and Jiyeon would be making solo debuts, they are considering promoting simultaneously, but also considering having Jiyeon promote in early April and Hyomin promote in early May. On March 28 it was announced that Jiyeon would start promoting on April 30 with single 1MIN,1SEC. On the 2nd of June Hyomin's second teaser and album title was released. The EP will be called Make Up with the lead single "Nice Body".
2009: I Really Really Like You and Invincible Youth
In November 2009, Hyomin was cast in the musical production of "I Really Really Like You", an adaption of the hit drama "Love Truly". Fellow member Boram was cast in the same musical in December 2010 alongside her father Jeon YoungRok.
Hyomin was a fixed cast member of KBS's variety show, Invincible Youth, from October 23, 2009 to December 24, 2010. She was one of the seven original members and one of the four that remained after the show experienced member changes.
2010-2011: My Girlfriend is a Nine-Tailed Fox and Gisaeng Ryung
In early 2012, Hyomin was cast in the musical "Our Youth Roly-Poly" along with group members Jiyeon and Soyeon. Hyomin was also cast in the Chinese version of We Got Married, in which her partner is Fu Xinbo, a Chinese idol. In Summer 2012 Hyomin was once again cast as a gumiho in MBC's fantasy sitcom, "The Thousandth Man". On February 10, 2013, Hyomin was cast in the Japanese film "Jinx". Her character, Ji-Ho, is a Korean exchange student at a Japanese university who gets two of her friends there to date.
During T-ara's "Roly-Poly" promotions in June 2011, Hyomin designed her own stage costume, which flaunted a retro pattern and short shorts that were popular during the period.
Hyomin launched an exclusive clothing collection, in collaboration with celebrity stylist Kim Sung-il, for G-Market on June 4, 2012. Hyomin has come up with a total of 150 products for the collection, and has been actively involved with the planning, designing, and product launch preparations for the shop.