She wrote the popular television dramas Lovers in Paris (2004), Secret Garden (2010), A Gentleman's Dignity (2012), The Heirs (2013), Descendants of the Sun (2016), Guardian: The Lonely and Great God (2016–2017), Mr. Sunshine (2018), and The Glory (2022–2023).

The cast and crew flew to France to film several scenes in Paris and Nice, igniting a trend among Korean dramas for overseas location shoots.

A Cinderella-like story of a cheerful, ordinary girl who becomes the housekeeper of a cold and suave businessman, lead actors Park Shin-yang and Kim Jung-eun shared the Grand Prize ("Daesang") at the 2004 SBS Drama Awards.

Directed by Kwak Ji-kyoon, it starred Ji Hyun-woo as a high school student who falls for a girl with a terminal illness (Im Jung-eun).

[7] A love story between the rich, arrogant and eccentric president of a department store (Hyun Bin) and a brave but sweet stunt woman (Ha Ji-won) whose bodies switch souls whenever it rains, Secret Garden (2010–2011) became one of the biggest hits of Kim's career.

She and the crew were so determined to cast him in the lead that not only was the airdate moved back from March to late May to accommodate his schedule, but Kim, in the hopes of getting him to take the role, lied to Jang's wife, actress Ko So-young that there would be no kissing scenes.

[16][17] Kim said the biggest difference was writing about 18-year-olds when her previous characters had been in their thirties and forties, calling The Heirs "a teen romance for grown-ups".

'"[18] Three years since The Heirs, Kim Eun-sook announced that she would be coming back with a human melodrama about a man and a woman who bond gradually as they save lives in disaster zones and end up falling in love.

However, in an interview, Kim Won-seok (co-writer of Descendants) stated that said there were some parts that could have been improved on if the show had been shot as it was being aired, per local industry norm.

[21] Following the success of Descendants of the Sun, Kim Eun-sook wrote her next two dramas, Guardian: The Lonely and Great God and Mr. Sunshine for cable network TVN in 2016 and 2018.

But not only do most of her dramas appeal to a wide age range of viewers and receive high ratings, but they often have that extra element that make them pop-culture buzz projects, whether it's due to a particularly catchy line of dialogue or a recurring joke.

[30] On March 10, 2022, Kim made a donation ₩60 millions to the Hope Bridge Disaster Relief Association to help the victims of the massive wildfire that started in Uljin, Gyeongbuk and has spread to Samcheok, Gangwon.

[31] On August 17, 2022, Kim donated ₩20 million to help those affected by the 2022 South Korean floods through the Hope Bridge Korea Disaster Relief Association.

[32] On March 7, 2023, Kim donated ₩20 million to the Hope Bridge National Disaster Relief Association to help in the restoration of Guryeong Village after a fire.