He first gained media attention when he appeared in the group's pre-debut "Big Bang Documentary," along with members G-Dragon, T.O.P, Taeyang, Daesung and Seungri.

Fellow Beast member, Yoon Doo-joon decided to become a singer after watching the BigBang documentary featuring Hyunseung.

[11] Hyunseung later met future fellow band member Yang Yo-seob while they were working as dancers for a show performance team.

In December 2010, Hyunseung teamed up with fellow member Lee Gi-kwang in a sub-unit to write and compose an R&B track as part of the group's digital album, My Story.

He performed as the lead character, Clyde, from April 15 to June 29, 2014 at the BBC Art Center along with other artists, including SHINee‘s Key, ZE:A‘s Park Hyung Sik, Kahi, and Oh So Yeon.

In April 2016, Hyunseung was nominated and won "Best Male Artist (South Korea)" at the 4th Annual V-Chart Music Awards in China.

[19] On July 29, 2016, Cube Entertainment announced that Hyunseung would be joining the dance competition program Hit The Stage, making it his first broadcast appearance since leaving Beast.

[24] In December 2020, Hyunseung is set to release a song digitally, titled "I want to wrap your cold hands warmly".

[25] On December 17 2020, the song was released on digital charts and YouTube called "I Just Can't Stop Loving You (Korean title: 차가운 너의 손을 따스히 감싸주고 싶어).