To the Beautiful You

Hwang Gye-bong/Director Sawatari

Na Cheol-soo/Oscar Himejima, tleader of Dormitory 3, the theater and arts department.

Director Jang, the perfectionist manager of sports management agency that Tae-joon is signed to.

Song Jong-min/Senri Nakao, a hurdler who is friends with Eun-gyeol. Although Jong-min constantly annoys Jae-hee, he is actually a warm hearted person.

Baek Gwang-min, the harsh and strict track-and-field coach.

Goo Jae-hee/Mizuki Ashiya, a South Korean girl who lived in the US since she was five. Jae-hee becomes lovestruck with Kang Tae-joon after witnessing him compete in a high jump event. Determined to see him jump again, she disguises as a teenage boy and transfers to the all-male Genie High School.

Kang Tae-joon/Izumi Sano, is a good-looking high jump athlete who holds the best record in the World Junior Championships. However, an injury ended his career. He was the second person after Jang Min-woo to learn Jae-hee is a girl by overhearing an argument between her and Daniel.

Cha Eun-gyeol, a charming soccer player who likes to joke around and possesses outstanding soccer skills. Eun-gyeol meets and falls in love with Jae-hee, causing him to doubt his sexuality.

Ha Seung-ri/Minami Nanba, the leader of Dormitory 2 and track team captain with strong leadership skills who later falls in love with Seol Ha-na.

Min Hyun-jae/Makoto Kagurazaka, a high jump athlete in the national team who is Tae-joon's rival and Eun-gyeol's roommate.

Jo Young-man/Megumi Tennoji, the leader of Dormitory 1 and Taekwondo department. He seems rough on the outside, but is actually passionate about helping his underclassmen.

Seol Han-na/Hibari Hanayashiki, a wealthy gymnast and a childhood friend of Tae-joon, who knows him better than anyone else. Although Han-na seems spoiled and insolent, she possesses a sincere affection for Tae-joon. Later, after sustaining ankle injuries, Han-na gives up her feelings for him and accepts Seung-ri's feelings.

Kang Geun-wook/Takehiko Sano, Kang Tae-joon's wealthy father. He is cold to his son on the outside, but actually cares for him very much.

Daniel Dawson/Shizuki Claude Ashiya, Jae-hee's caring older half-brother who works as a doctor. Although Daniel is adamant on taking Jae-hee back home after discovering what she did, he eventually relents and allows his sister to continue to study in Genie High

Hong Da-hae, an aspiring violinist and a childhood frenemy of Eun-gyeol.

John Kim/Gilbert Lang, Jae-hee's childhood friend who works as a photographer and aided her in transforming into a boy to enter Genie High School. He loves Jae-hee, but ended up being the catalyst that makes Tae-joon realize that she is an important special person in his life.

Student on dormitory 3 (Ep. 3 & 7)