In Seong Jeong

Jeong In Seong

  • Name: Jeong In Seong
  • Native name: 정인성
  • Also Known as: JungSung, Jung In Sung
  • Nationality: South Korean
  • Gender: Male
  • Born: July 1, 1994
  • Age: 31
Jeong In Seong is a South Korean singer, dancer, musical actor and member of KNK (크나큰). He graduated from Korea Arts High School. Before debuting, he spent several years as a trainee at Big Hit Entertainment and FNC Entertainment.

After arriving at YNB Entertainment (YNB엔터테인먼트), he appeared in music videos of their label mate, BESTIE, and also performed as a backup dancer.

He made his debut in February 2016 as the group's main vocalist with a showcase and the release of their first single, "Knock".

In mid-2018, YNB faced financial problems, and the company ceased operations, leaving the members without a contract and an agency. In early 2019, they signed with 220 Entertainment (220엔터테인먼트) and had several tours in the US and in Europe. However, after the promotion of their third EP, the group went on hiatus.

He debuted as an actor with a minor role in "20th Century Boy and Girl" in 2017 and had the lead role in the musical "All Eyes On Me".

He enlisted in his mandatory military service on February 8, 2022, and was discharged on August 7, 2023.

He made his debut as a solo artist in October 2023 with the digital single "Trust Yourself".

(Source: kisskh) Edit Biography
Drama
Year Title # Role Rating
2021 Dali & Cocky Prince
Korean Drama, 2021, 16 eps
[Himself - KNK member] (Ep. 7) (Guest Role)
16
[Himself - KNK member] (Ep. 7)
Guest Role
8.4
2017 20th Century Boy and Girl
Korean Drama, 2017, 32 eps
[Boys Be Ambitious idol group member] (Guest Role)
32
[Boys Be Ambitious idol group member]
Guest Role
7.8
TV Show
Year Title # Role Rating
2024 Build Up: Vocal Boy Group Survivor
Korean TV Show, 2024, 10 eps
[Contestant] (Regular Member)
10
[Contestant]
Regular Member
8.0
2020 Question Mark
Korean TV Show, 2020, 143 eps
(Ep. 34) (Guest)
143
(Ep. 34)
Guest
0.0
2019 Good Friends
Korean TV Show, 2019, 20 eps
(Ep. 9-10) (Guest)
20
(Ep. 9-10)
Guest
6.0
2019 Q&A Machine
Korean TV Show, 2019, 34 eps
(Ep. 5) (Guest)
34
(Ep. 5)
Guest
7.6
2019 Player 7
Korean TV Show, 2019, 21 eps
(Ep. 18) (Guest)
21
(Ep. 18)
Guest
7.9
2019 Idol Lunch Box
Korean TV Show, 2019, 10 eps
(Ep. 8) (Guest)
10
(Ep. 8)
Guest
0.0
2019 Aja Aja Tayo! Season 2
Filipino TV Show, 2019, 12 eps
(Ep. 11-12) (Guest)
12
(Ep. 11-12)
Guest
10.0
2018 2018 Idol Star Athletics Championships
Korean TV Show, 2018, 4 eps
(Regular Member)
4
Regular Member
7.8
2017 MIXNINE
Korean TV Show, 2017, 14 eps
[Contestant] (Regular Member)
14
[Contestant]
Regular Member
7.0
2017 My KNK TV Season 2
Korean TV Show, 2017, 34 eps
(Main Host)
34
Main Host
9.5
2017 Fantastic Duo Season 2
Korean TV Show, 2017, 36 eps
(Ep. 29-30) (Guest)
36
(Ep. 29-30)
Guest
7.9
2017 K-RUSH
Korean TV Show, 2017, 20 eps
(Ep. 9-10) (Guest)
20
(Ep. 9-10)
Guest
8.0
2016 2016 SBS Gayo Daejeon
Korean TV Show, 2016, 1 eps
[Performer] (Regular Member)
1
[Performer]
Regular Member
7.9
2016 Hitmaker Season 3
Korean TV Show, 2016, 6 eps
(Guest)
6
Guest
7.7
2016 Fact iN Star
Korean TV Show, 2016, 200 eps
(Ep. 9, 40) (Guest)
200
(Ep. 9, 40)
Guest
8.2
2016 The Immigration
Korean TV Show, 2016, 13 eps
(Guest)
13
Guest
7.9
2016 Duet Song Festival
Korean TV Show, 2016, 47 eps
[Panelist] (Ep. 12) | [Performer] (Ep. 22) (Guest)
47
[Panelist] (Ep. 12) | [Performer] (Ep. 22)
Guest
8.2
2015 My KNK TV
Korean TV Show, 2015, 70 eps
(Main Host)
70
Main Host
8.7
2015 King of Mask Singer
Korean TV Show, 2015, 525 eps
[Contestant] (Ep. 215) | [Panelist] (Ep. 281-282) (Guest)
525
[Contestant] (Ep. 215) | [Panelist] (Ep. 281-282)
Guest
8.0
2013 Cheongdamdong 111
Korean TV Show, 2013, 8 eps
(Regular Member)
8
Regular Member
7.3
2013 After School Club
Korean TV Show, 2013, 671 eps
(Ep. 210, 241, 266, 351, 378) (Guest)
671
(Ep. 210, 241, 266, 351, 378)
Guest
7.8
2011 Weekly Idol
Korean TV Show, 2011, 707 eps
(Ep. 256, 296) (Guest)
707
(Ep. 256, 296)
Guest
8.1
2011 Immortal Songs: Singing the Legend
Korean TV Show, 2011, 750 eps
(Ep. 294) (Guest)
750
(Ep. 294)
Guest
8.2
2010 Hello Counselor
Korean TV Show, 2010, 431 eps
(Ep. 285) (Guest)
431
(Ep. 285)
Guest
7.9
2010 Running Man
Korean TV Show, 2010, 850 eps
(Ep. 319) (Guest)
850
(Ep. 319)
Guest
9.2
Trending Articles
K-netz call for boycott of 'Can This Love Be Translated?' over THIS actor's casting
News - Dec 24, 2025

Netflix's 'Can This Love Be Translated?' embroiled in a controversy ahead of its premiere

IU and Byeon Woo Seok's 'Perfect Crown' drops teaser
K-Drama - Dec 31, 2025

'Perfect Crown' unveils special teaser

Kim Seon Ho becomes Go Youn Jung's interpreter in 'Can This Love Be Translated?'
K-Drama - Jan 5, 2026

'Can This Love Be Translated?' unveils stills featuring Go Youn Jung and the official trailer

Im Ji Yeon transforms into a Joseon villainess in 'Brave New World'
K-Drama - Jan 1, 2026

SBS unveils teaser for 'Brave New World'

Hyun Bin and Son Ye Jin wrap up the year with a generous donation
News - Dec 30, 2025

Hyun Bin and Son Ye Jin demonstrated their generosity with a year-end charitable donation.

Kim Ji Won plays a genius surgeon in 'Doctor X: Age of the White Mafia'
K-Drama - Jan 1, 2026

Check out the teaser for 'Doctor X: Age of the White Mafia'

Reasons To Enjoy Typhoon Family
Recaps - Jan 3, 2026

This time around I'm going to tell you diferent reasons about a vintage story set in the '97 with and an amazing cast, entrancing cinematophy that will keep you glued to your seats, called "Thyphoon Family" aired during the cold nights of autumn!

Veteran actor Ahn Sung Ki passes away at 74
News - Jan 5, 2026

Details inside

Jeong In Seong

In Seong Jeong
0 Followers
38 Hearts

Details

  • First Name: In Seong
  • Family Name: Jeong
  • Native name: 정인성
  • Also Known as: JungSung, Jung In Sung
  • Nationality: South Korean
  • Gender: Male
  • Born: July 1, 1994
  • Age: 31

Weekly kisskh Support Goal

13%
Help Support kisskh

Top Contributors

11 edits
7 edits
3 edits
3 edits

Popular Lists

Related lists from users
Idolboys
45 people 24 loves
My Bias List
63 people 9 loves