K-Pop Idols from SM Entertainment with the Longest Training Period Each Generation

In the early 2000s, the long trainee period had already become part of the SM system. One example is Kim Junsu, who later debuted with TVXQ. He underwent training for 5 years, from 1999 to 2004. This period became the foundation before he officially appeared as an early generation SM idol.

Not long after that, Leeteuk also recorded a long journey before debuting. He was a trainee for 5 years, from 2000 to 2005. After completing his training period, he debuted with Super Junior. This process demonstrates SM's consistency in implementing a long-term training system.

The name Jessica Jung also drew attention due to her trainee period lasting 7 years. She underwent training from 2000 to 2007 before officially debuting. Jessica was then introduced as a member of Girls' Generation. The length of this process showcases the strict selection standards that SM applies to potential female idols.

Unlike some of his seniors, Jonghyun had a relatively shorter trainee period. He underwent training for 3 years from 2005 to 2008. After that, he debuted with SHINee. Although shorter, this period still went through the strict training system typical of SM.

Sulli was part of the list of idols with a medium trainee period. She trained for 4 years, from 2005 to 2009. After completing her trainee period, she debuted with f(x). This experience became an important part of her career formation in the K-Pop industry.

Suho is one of the idols with the longest trainee period in his generation. He trained for 7 years from 2005 to 2012. After going through this long process, he debuted with EXO. The length of this training period is evidence of his dedication and patience before performing on the global stage.

Seulgi became one of the female idols with the longest trainee period at SM. She underwent training for 7 years from 2007 to 2014. This period was completed before she officially debuted as a member of Red Velvet. The length of the training period further emphasizes the strict selection and training system at SM.

Johnny recorded one of the longest trainee periods in SM's history. He trained for 9 years, starting in 2008 until he finally debuted in 2017. He was then officially introduced as a member of NCT. This nearly decade-long duration has made his name often mentioned as the longest trainee at SM.

In the next generation, Ningning trained for 4 years. She trained from 2016 to 2020 before being announced for debut. After that, she appeared as a member of aespa. This period shows that the long training system is still maintained up to the latest generation.

Eunseok is recorded to have undergone a trainee period of 6 years from 2017 to 2023. This period became a stage for developing his vocal, rap, and performance skills before officially debuting. After going through that long process, he was introduced as a member of RIIZE. His name then joined the list of SM idols with a lengthy training period in the latest generation.

The latest name in the spotlight is Yuha. She has undergone a trainee period of 8 years, from 2017 to 2025. Yuha then debuted with Hearts2Hearts. This long duration once again emphasizes SM's reputation as an agency with the strictest and longest training system. Come on, read other articles about K-Pop idols on Kapanlagi.com. If not now, when, KapanLagi?