She is best known for playing the youngest of the three sisters in sex comedy film Everybody Has Secrets (2004), a con artist in the television drama Private Lives (2020), and a top star in Castaway Diva (2023).

[7] Though she continues to act in mainstream films and TV dramas such as Mary Stayed Out All Night, in recent years Kim has become more adventurous in her choice of projects.

Kim said portraying a bisexual in Five Senses of Eros (later expanded to In My End Is My Beginning) and a lesbian in Life is Peachy was not a problem for her: "I approached the film in this way: Two people meet and fall in love.

[17] After appearing in Im Sang-soo's erotic suspense drama The Taste of Money,[18] Kim starred opposite Hidetoshi Nishijima in the Korea-Japan joint production Genome Hazard, a film adaptation of Tsukasaki Siro's same-titled sci-fi mystery novel.

[22] In 2021, Kim acted as Kyung-eun, Jung-soo's (Park Byung-eun) first love,[23] in Lost, a 2021 television series starring Jeon Do-yeon and Ryu Jun-yeol.

[32] One of the few Korean star couples who openly admitted their dating status, they are very active in charitable organizations, and in 2011 were both appointed as honorary ambassadors for World Vision.

[33][34][35] They announced their engagement in August 2011 (Kim reportedly turned down a movie role to prepare for her upcoming nuptials),[36][37][38][39][40] and subsequently released pre-wedding photos.

[44] The ceremony was officiated by the president of World Vision Korea; Yoo and Kim then donated a portion of their monetary gifts to the organization to help build an elementary and middle school in Myanmar.