In the Jung Jong era of the Chosun Dynasty, little Jang Geum decides to work in the palace and enters the palace as her mother asked her to in her last wish before she died, after having been taken care of by Gang Duk Goo, Dae Ryeong Suk Soo. As a one big curious cat who cannot keep her curiosity under control and has to see for herself whatever she needs to know, Jang Geum sometimes makes mistakes. But she impresses people with her exceptionally delicate palate and cooking ability and is recognized by Han Sang Gung, her master and mentor for her talent.

One day, she finds out that Han Sang Gung was her mother¡¯s best friend when they two were Na In, one of the junior titles for female workers in the palace, and they become very close. On the day of Royal Competition to select the best Sang Gung of the Soo Ra Gan, Han Sang Gung could not enter the palace due to the plot of Choi Pan Sool, but Jang Geum competes with Choi in Han¡¯s place and takes the honor of being the best Sang Gung, a senior position of the titles held by female palace employees. However, Han and Jang Geum become involved in a duck dish accident again due to the malicious plot of Choi Pang Sool and Choi Sang Gung. As a result, they are sent into exile in Jeju Island and Han dies on the way to the island. While living as a government servant in Jeju, Jang Geum meets a medical assistant Jang Duck and returns to the palace after learning the medical skills from Jang Duck. After she becomes a medical assistant, Choi Sang Gung and her family continue to make every attempt to kick Jang Geum out of the palace. But each time, Jang Geum beats them with sincerity and integrity in her medical practice and becomes absolutely trusted by the queen by proving her outstanding medical knowledge and skills in many instances. She makes her name by performing many acts of medical miracles such as curing serious patients that even senior medical officials cannot cure, and despite all the hardships, manages to become the royal doctor for King Jung Jong, beating so many male competitors.