Kim family •
Kim Kap-soo as Director Kim •
Park Mi-sun as Park Mi-sun •
Kim Young-ok as Kim Young-ok •
Kim Hye-ok as Kim Hye-ok/Kim Gab-sun (Ep. 120–210) •
Jo Kwon as Hwang Ok-yub •
Ga-in as Hwang Geum-ji (Ep. 1–135) •
Yoon Seung-ah as Kim Saet-byul •
Jun Tae-soo as Jeon Tae-soo (Ep. 1–60) •
Jin Yi-han as Jeon Tae-poong (Ep. 83–210) • as Butler Kim
Bang family •
Bang Eun-hee as Bang Eun-hee (Ep. 2–210) •
Yeon Woo-jin as Bang Woo-jin •
Yoon Doo-joon as Yoon Doo-joon (Ep. 3–210) •
Park Soo-ah as Park Soon-deok (Ep. 64, 78–210) •
Kim Na-young as Kim Na-young • as Han Young (Ep. 67–210)
Extended cast •
Park Cho-rong as Cho-rong (Ep. 125–210) • as Teacher Jung (Ep. 1–86) • as President Choi • as Director Lee • Hong Soon-chang as Kim Gab-sub, Director Kim's cousin (Ep. 129) •
Choi Hyo-eun as Jin-ah
Cameo appearances •
Yoon Jong-shin as tutor •
Nine Muses as Director Kim's fan girls (Ep. 6) •
Nichkhun as Ok-yub's human substitute (Ep. 16) • as double eyelid surgery patient (Ep. 18) •
Han Sun-hwa as Geum-ji's friend (Ep. 24) •
Shindong as Geum-ji's blind date (Ep. 43-44) • as Doo-joon's classmate (Ep. 70) • as billiards player (Ep. 72) •
Kim Shin-young as Kim Se-byul, the maid (Ep. 77) •
Leeteuk as Seung-ah's blind date (Ep. 143) •
David Oh as English teacher (Ep. 154) •
Bang Si-hyuk as audition judge (Ep. 160) •
Uee as Kim Yu-jin (ep 182, 210) •
Lee Gi-kwang as Doo-joon's rival in love (Ep. 193) •
Jo Young-min as high school student •
Jo Kwang-min as high school student •
Minwoo as high school student ==Notes==