After graduating with a degree in education from Sungkyunkwan University, Moon So-ri became part of the theater group Hangang ("Han River") from 1995 to 1997, and debuted in the play Classroom Idea (she also collaborated in its creation).

[1] She appeared in plays and short films such as Black Cut[2] and To the Spring Mountain[3] before finding fame as a leading actress.

A 180-degree turn from her previous screen image, this film featured her as a free thinking woman in a decaying marriage who starts an affair with the teenage boy next door.

She then narrated My Heart Is Not Broken Yet, a documentary on Song Sin-do and her decade-long lawsuit against the Japanese government for an official apology towards her fellow comfort women.

[16][17] She followed that with sports movie Forever the Moment (a sleeper hit in 2008),[18][19][20] another TV drama (about a family of grown-up siblings),[21] and the human rights-themed Fly, Penguin in 2009.

[42] Because she found his script "unique and creative," Moon took a risk on newbie director Park Myung-rang and joined the cast of his 2013 crime thriller An Ethics Lesson.

[48] She also appeared in Park Chan-kyong's fantasy/documentary Manshin: Ten Thousand Spirits that looked at Korean modern history through the checkered past and exorcism-based imagination of a shaman.

[51][52] Moon then made her directorial debut with the short film The Actress, in which she played the title character who goes mountain climbing with friends then meets up for drinks with a group of male acquaintances; once alcohol has loosened the tongues of her companions, she learns their prejudices against her.

[58][59] The following year, she was invited to the Venice International Film Festival, where she became the first South Korean actor to serve as a juror on the Orizzonti section.

[61] In 2018, Moon starred in the Korean film adaptation of the Japanese manga series Little Forest, playing the main character (Kim Tae-ri)'s mom.

[71][72][73] Both Sungkyunkwan University alumni, the two reportedly met when Jang directed her in the 2003 music video for Jung Jae-il's 눈물꽃 ("Flower of Tears").