She began her career as an acclaimed actress in theater, then transitioned to supporting roles on television and film, notably in works by director Jang Jin.

In 2013, she played her first onscreen leading role in the revenge crime thriller Azooma,[3][4] which won her the Best Actress Award from the Director's Guild at the 17th Busan International Film Festival (BIFF).

[5][6] Jang, a graduate of Seoul Institute of the Arts, began her career in the Mokhwa theater company in 1995 after being recommended by her college senior Seong Ji-ru.

She wanted to make money, so She started working as a clerk at a clothing store, but soon She missed theater so much that She couldn't stand it.

[6] In 2005, Jang participated in the Berlin Asia-Pacific Week event with the play 'Princess Bari', returning only in October after performing in Germany.

Notably, Jang Young-nam's acting skills reached their zenith in the one-person play 'Vagina Monologue', where she impressively portrayed nine different roles with great intensity.

She played the main character in "Clumsy People" (December 7, 2007 – March 16) directed by director Jang and performed at Daehakro's largest theater festival, 'Play'.

She received endless love calls from the theater world, including an offer to appear in "Agarwood" (June 10–28, directed by Shim Jae-chan).