Early career A year after graduating, Son joined the Yeonwoo Theater Company. Within six months, she debuted as a theater actress in the 2007 play
Haemoo (also known as
Sea Fog). In 2009, Son joined the cast of
Gil Sambongdeum as Maeng-hwa. This work was a collaboration between writer Kim Min-jung and director Ahn Kyung-mo, who had previously worked together on the 2007 play
Haemoo. The play was produced by Yeonwoo Theater Company and Namsan Arts Center as part of the Namsan Arts Center's 2009 Season Program. In late 2009, Son co-starred alongside Min Jun-ho in the romantic comedy play
A Dramatic Night. She portrayed Si-hoo, while Min Jun-ho played Jeong-hoon. The play explored the subtle psychological changes between its male and female leads, focusing on a one-night stand. The Yeonwoo Theater Company presented this performance, which was written by Hwang Yun-jeong and selected for the 2009 New Year's Literary Arts Festival. The play was directed by Lee Jae-jun, who had won both Best Director and Best Picture at the 2007 Miryang Summer Performing Arts Festival's Young Director's Home Awards.
A Dramatic Night premiered at Yeonwoo Theater in Daehangno, running from December 16, 2009, to January 17, 2010. In 2010, Son auditioned for the play
Rooftop House Cat, an adaptation of a web novel previously made into an MBC drama series of the same name. She was triple-cast as Nam Jeong-eun, the female lead, alongside Hwang Bo-ra and Kim Yeo-jin, in the play's first season. The play was directed by Kim Tae-hyung, with Sung Tae-joon playing opposite Son as Lee Kyung-Min.
Theater Ganda In 2013, Son reunited with Min Jun-ho for the premiere of his play
Me and Grandpa. The play had a reading performance at the Namsan Drama Festival on February 21, 2013. Son shared the role of Jun-hee's grandmother with Jeong Seon-ah, who had participated in the reading performance alongside
Jin Seon-gyu (as grandfather),
Oh Eui-sik (as Jun-hee), and Lee Seok (as writer). The cast for the premiere included Oh Yong-lee (as grandfather), Hong Woo-jin (as Jun-hee), and
Yang Kyung-won (as writer). It ran from July 11 to August 4 at the Daehangno Information Center. In the end of the same year, Son was invited as one of representative actress of
Daehak-ro, in 'Ganda GO', a project by the Ganda theater company, as part of their 10th-anniversary celebration. The first work presented was
Almost Maine by
John Cariani.
Working with Kim Tae-hyung/No Name In 2013, Son collaborated once again with Director Kim Tae-hyun in play
The Age of Love (2013), which was an adaptation of ''
Hisashi Nozawa's'' best-selling Japanese novel. She shared the leading female role of Haru, a sports center instructor, with actresses
Hwang In-young and
Shim Eun-jin. In 2014, Son had her first collaboration with the Noname Theater Company for the Korean premiere of
Fight of Cocks written by a young British playwright
Mike Bartlett. The play explores the weighty subject of "subjectivity and choice" through the character of John, who must make a decision between a man and a woman due to gender identity confusion. The play garnered attention during its UK premiere in 2009 for its cast, including Ben Whishaw. It won the
Lawrence Olivier Award in 2010, and was performed off-Broadway in New York in 2012. In the Korean production, actor
Park Eun-seok was cast as John and Son Ji-yoon appeared as W, John's new lover of the opposite sex. The other cast members included Kim Jun-won and Seon Jong-nam. The play ran at Doosan Art Center Space 111 in Seoul from July 11 to August 3, 2014, and received a warm response. Derived from the English expression of OCD (Troubles Obsessionnels Compulsifs, TOC), Toc Toc is a riotous comedy about obsessive-compulsive patients. The play was written by
Laurent Baffie, a famous French writer, actor, and TV show host. In 2017, Son reprised her role as W in the encore performance of
Fight of Cocks alongside fellow actor Seon Jong-nam, who played F in the original premiere. Lee Myung-haeng and Lee Tae-goo joined the production as new cast members. The play involved "character juggling" as five actors onstage seamlessly transformed into various roles, including the centenarian protagonist Alan and the individuals he encounters. Son portrayed characters such as elephant, a gang boss, a director, a guard, also 'Allan 3'. This production marked the first time Son and Lee Jin-hee shared a stage. In their previous projects together, They usually engaged in double casting, alternating their appearances in the play. In 2018, Son participated in the 4th encore performance of Capone Trilogy at the Hongik University Daehak-ro Art Center. She shared the role of Lady with actress
Kim Ji-hyun and Choi Yu-ha. The other cast members included Lee Seok-jun, Kim Jong-tae, and Kim Joo-hyun, who played the role of Oldman. The role of Young-man was shared by Kim Do-bin, Kang Jung-woo, and Yoon Na-mu.
The Pride is the debut work of Greek-British author
Alexi Kaye Campbell, which premiered in 2008 at the
Royal Court Theatre Upstairs and received critical acclaim. The South Korean adaptation, written by Ji Yi-seon and translated by Kim Soo-bin, premiered at
The 5th Best Plays Festival at Art One Theater in 2014. In 2020, Son Ji-yoon portrayed the dual roles of Daisy and Claire in
Wife, a play by British playwright
Samuel Adamson. The production, presented by the Seoul Metropolitan Theater Company, featured a talented ensemble cast including Lee Joo-young, Oh Yong, Baek Seok-gwang, Jung-hwan, Woo Beom-jin, and Song Gwang-il. Directed by Shin Yoo-chung, the play explores the growth of women and evolving perspectives on sexual minorities. It begins in the last scene of
Henrik Ibsen's ''
A Doll's House and spans four eras from 1959 to 2042. The encore performance of Wife'' was staged at the S Theater, Sejong Center for the Performing Arts from July 30 to August 2, 2020. Son reprised the role from August 8 to 23 at Daehakro Arts Theater Grand Theater. In 2021, Son and Woo Jung-won were double-cast in the role of C in the play
The Dressing Room (Gakuya). C, who portrays the character Nina, which is a character who constantly memorizes lines in the dressing room and maintains a state of tension. The play is a renowned work by
Kunio Shimizu, a famous Japanese playwright who died in April of that year. == Personal life ==