2009–2012: Breakthrough
In 2009, she starred opposite Yoo Ji-tae in the drama Star's Lover, playing a top actress who falls in love with an ordinary man. Choi received ₩48 million per episode, the highest salary for a Korean actress at the time (her record was later broken by Go Hyun-jung's ₩55 million for the 2010 drama Daemul).
That same year, she set up her own management agency called C,JW Company with her brother as CEO. She also joined the ensemble cast of semi-improvisational mockumentary Actresses, arguably her most significant film yet.
During the press conference for the 2011 series, Can't Lose, co-starring Yoon Sang-hyun, featuring a lawyer couple facing their own divorce suit, she was asked if she worried about shedding her pure and innocent image. Choi said, "I've had the same image for 15 years. Isn't it time for me to break out? I was a melodrama queen and now I want the title of romantic comedy queen." She added that she had gained more fans after showing her cheerful, easygoing side as a guest on the reality show 2 Days & 1 Night.
In 2012, Choi was cast in the Chinese drama City Lovers, in which she portrayed the CEO at an event management company opposite Qin Hao, a newly employed businessman at her firm.
Later that year, she became the host of Choi Ji-woo's Delicious Korea on food lifestyle cable channel O'live TV alongside fashion designer Jung Kuho. The 5-episode show, which aired from November 23 to December 21, 2012, aimed to promote Korean cuisine and culture to the world, and the two hosts traveled through South Korea and introduced little-known regional food to the viewers.
She next headlined the 2013 remake of the hit 2011 Japanese drama Kaseifu no Mita. In The Suspicious Housekeeper, Choi played the titular character, an icy and stoic yet amazingly capable housekeeper who comes to work for a recently widowed father and his four children. Despite the difficulty of not being able to react to her costars, Choi said she chose the role because she "was really charmed by the way the heroine refrains from letting her emotions show."
