He is one of the members of the South Korean boy group VIXX, and has been widely praised for his unique, soulful, and husky vocal tone.

He later performed and won more singing competitions in middle school as part of a team with his friends[3] prior to debuting with VIXX.

Despite lacking experience in dance, Ken was able to pass his audition to Jellyfish Entertainment because of his singing where he trained for five months before debuting with VIXX.

[9] In 2013, Ken made a cameo appearance in episode four of SBS' television drama The Heirs alongside his group members.

[11] In 2014, the singer landed his first acting role as a main cast member in the television comedy drama MBC Every 1's Boarding House No.

[13] For the role, he had to sing at a lower register, a sharp contrast from the high notes that predominantly appear in VIXX's music.

The project which has included artists like Seventeen's vocal unit and Epik High's Tablo, the single "Over Sleep" was released on May 30, 2016.

[20][21][22] On December 22, 2016, Ken contributed to The Legend of the Blue Sea soundtrack with the song "Fool" (Korean: 바보야).