The lead role of Seo Jang-geum was initially offered to actresses Song Yoon-ah and Jang Jin-young, but both declined for personal reasons before Lee Young-ae was finally cast after some twists and turns.

The role of Choi Keum-young was originally set for Kang Sung-yeon, who backed out after being cast in KBS's She's Great, prompting MBC to formally protest; the offer then went to Jung Sun-kyung, who also declined due to another drama commitment.

Kyeon Mi-ri was originally cast as Lady Han but ended up playing Lady Choi instead, after the actress originally slated for Lady Choi, Song Chae-hwan, left the production for personal reasons and Yang Mi-kyung stepped in to take over the Lady Han role.

The character of Jang-geum is loosely based on a real historical figure mentioned about ten times in the Annals of King Jungjong, where she is recorded only as a trusted royal physician; almost all other details about her life in the drama were invented by the screenwriter.

The series became one of the primary drivers of the Korean Wave, being exported to 91 countries and earning an estimated US$103.4 million worldwide after being produced for about US$15 million.

In China, Hunan TV bought the broadcasting rights for US$10,000 per episode, and the show's ratings reportedly peaked at 180 million viewers, generating unprecedented profits for the network.

The original broadcast run was extended from 50 to 54 episodes, a decision reportedly made to allow more time to finalize casting for MBC's following drama, Phoenix.

The outdoor sets built for the show in Yangju became South Korea's first drama theme park, opening to the public in December 2004, but it was closed in December 2011 due to safety concerns since it had originally been built only as a temporary set rather than a public attraction.

The theme song 'Onara' is written in archaic Korean, which sparked public debate over the meaning of its lyrics until songwriter Im Se-hyeon eventually clarified them himself.

For international releases, the theme song was reworked into multiple language versions, including Cantonese by Kelly Chen for Hong Kong, Mandarin by Angela Chang for Taiwan, and Sinhalese and Tamil versions for Sri Lanka using traditional instruments like the raban.

The show has been referenced or shown on-screen in numerous other series, including King of the Hill, Princess Hours, Love Truly, Who Are You, the Taiwanese drama Silence, and Playful Kiss.

In 2007, the drama was adapted into a stage musical called 'The Great Janggeum' at the Seoul Arts Center, condensing the 54 TV episodes into a two-and-a-half-hour show featuring 400 different traditional Korean costumes and 40 original songs by composer Cho Sung-woo.

A sequel, Dae Jang Geum 2, was announced by MBC in 2012, with writer Kim Young-hyun confirming plans in 2014 for lead actress Lee Young-ae to reprise her role after having turned down earlier sequel offers since her semi-retirement in 2006.