Main •
Namkoong Min as Kang Hoon-nam :The director of a toy gallery, and a relationship expert who doesn't believe in love. •
Hwang Jung-eum as Yoo Jung-eum :A diving athlete-turned "relationship helper" who dreams of love and marriage, but has given them up in the face of reality. •
Choi Tae-joon as Choi Jun-soo : A clinic doctor who is Jung-eum's best friend. •
Oh Yoon-ah as Coach Yang Sun-hee :Coach of the National Diving Team. • Jo Dal-hwan as Charlie :A magazine editor. •
Jung Moon-sung as Yook Ryong :Hoon-nam's cousin.
Supporting • Nam Kyung-eub as Kang Jung-do :Hoon-nam's father. A politician. •
Lee Moon-sik as Yoo Seung-ryul :Jung-eum's father. A positive and optimistic man who serves as a motivation to his daughter. •
Lee Joo-yeon as Lee Su-ji / Lee Susie :Daughter of the President of Korea Swimming Association, who came to Korea from Australia to search for Hoon-nam. •
Myung Ji-yun •
Baek Ji-won as Bong Sun-hwa :Jung-eum's manager at the matchmaking company. • Seo Dong-won • Seo Eun-woo •
Jin Ye-sol •
Kang Hui as Model
Special appearance • Jung Yong-joo as Oh Doo-ri :Jung-eum's potential client. •
Ji Il-joo •
Kim Kwang-kyu as Kim So-wool ==Production==