Lee Dae-yeon

as Gi-ha

as Han Na-hyun's Dad (3 episodes)

as Oh Daehan

as CSAT Supervisor / Choe Man-li

as Ma Seong-chun (12 episodes)

as Kang Ki-seok (131 episodes)

as Ho-seop

as Hyun-soo

as CEO

as Jang Hyun-seok (120 episodes)

as Baek Jun-shik (12 episodes)

as Cha Man-Jong (105 episodes)

as Father

as Lee Woong-seok (12 episodes)

as Shin Koo-Cheol (32 episodes)

as Han Young-Cheol (40 episodes)

as Woo Hyung-Man (16 episodes)

as Yoo Jung-Man (16 episodes)

as Ward Chief

as Professor Hwang (16 episodes)

as Yoon Dong-Chul (120 episodes)

as Lee Kyung-shik (53 episodes)