Hyoseong was later discovered by TS Entertainment through a show aired on SBS MTV called Diary of Five Girls and spent two years with the company as a trainee.

[5] She was then advised by an agent at Good Entertainment to audition for Mnet's "Battle Shinhwa" and was picked as one of the final twelve participants and among them, three were females.

[7][8] Good Entertainment had initially intended for Hyoseong to debut in a three-member group along with Yoobin and Uee, but ended up adding G.NA and Jiwon.

[6][8] In 2008, after "Five Girls" disbandment, she started working at a part-time job and managed to earn enough money to attend Inha University; however, her college life was short-lived.

In August 2010, they released their second mini album entitled "Madonna" and the title track continued their success as it topped the Gaon Single Charts.

[12][14] In January 2011, the group deviated from their "sexy" and "sassy" image and released "Shy Boy", a "cutesy" and retro inspired song.

[12] The title track became another hit for Secret as the song reached number one on the Gaon Monthly Singles Charts and won them another trophy in SBS's Inkigayo.

The accident, which ruptured the cartilage in her left knee and fractured the top of her right foot, halted her promotional activities with Secret.

[17] On the October 21, 2012 episode of Inkigayo, the live music show revealed a teaser video hinting that twenty of the most-wanted K-pop stars would transform into four new project groups in the yearly event.

Hyoseong will be part of the girl group Dazzling Red with Sistar's Hyolyn, 4minute's Hyuna, After School's Nana and KARA's Nicole.

Slated to air on December 29, the group will perform the tunes only one time on stage and the profits from online streaming and downloading of the songs would be donated to people in need.

In the same year, Hyoseong reprises her role as Han Na Young in the second season of Orion Cinema Network's drama, The Ghost-Seeing Detective Cheo Yong.

Find Me was promoted as the lead single which featured TS Entertainment labelmate D.Action from the hip-hop duo Untouchable.

On March 5, Hyoseong's lawyer revealed that she had filed a civil lawsuit against TS Entertainment in September 2017 to confirm that her contract with the agency is no longer valid.

TS Entertainment also transferred the management rights conferred by its exclusive contract with the singer to another party without the consent of Jun Hyoseong herself.

A representative of Tommy & Partners Entertainment stated "recently, Jun Hyoseong's exclusive contract with her former agency was ruled invalid.

While searching for a new agency in order to resume her activities in the entertainment industry, she ended up signing an exclusive contract with Tommy & Partners.

Jun Hyoseong is talented in many areas, including singing, acting, and variety, and we will not hold back in fully supporting her so that she can make a fresh start.

On November 14, The Seoul Western District Court ruled in Hyoseong's favor in her legal battle against TS Entertainment.

[45] On September 6, 2022, it was announced that Hyoseong would be releasing "Come to the Story of the Sea" as the travel theme song for the "2022 Welcome to Lively Incheon project.

According to a report by Sports Chosun, around 2:00 am in Korean standard time, the van that Secret rode in was filmed speeding down the highway by another vehicle with a camera.

However, a YTN News update revealed that although Hyoseong had injured her knee and had to wear a cast, it was a fellow Secret member, Jung Ha-na, who received the most serious injuries after breaking her ribs.

[47] In a follow-up television report by web portal Nate, a fellow Secret member Song Ji-eun explained how their leader, Hyoseong saved her life during the accident.

She said: Last year, after finishing our recording for Star King and heading home, our car was in an accident that caused it to flip over on the road.

However, the problem did not stop for TS Entertainment, who had to release a follow-up statement on their Twitter account, cautioning fans that Hyoseong does not use Facebook.

[55] Ilbe users use the term as their "down-voting button",[55] using "democratization" to mean 'the citizens create chaos', 'to destroy', or 'to make disappear'.

TS Entertainment uploaded a video of Hyoseong performing a cover of Beyoncé's Naughty Girl and Crazy in Love in Secret's 1st Japan Tour in March 2012.

Because of her work with Secret, she portrays a mix of cute and sexy image through their songs such as "Shy Boy" and "Madonna".

Along with Secret, Hyoseong has been featured as a model for various endorsement deals such as Grand Mer (Online Fishing Game),[58][unreliable source?

Along with Han Sunhwa, Kim Himchan and Bang Yong Guk, Hyoseong was chosen as a model for KELLAN sportswear 11/12 Winter Collection in September 2011.