Suh Jang-Geum (Lee Young-Ae)
Intelligent, beautiful, spontaneous, and endlessly curious, Suh Jang-Geum has overcome many hardships in life through her strong will and patience. After tragically losing her parents at the tender age of 10, she enters the Royal Palace and devotes herself to becoming the best cook in the King's employ. But false incriminations cause her to be driven out of the palace, and to live the life of a servant. Holding onto hope, Jang-Geum learns the medical arts and reenters the palace to become the first female physician to a king (King Jungjong) in the history of the Chosun Dynasty. In the annals of Korean history, she's now known as the "Great Jang-Geum"(Dae Jang Geum).

Min Jung-Ho (Ji Jin-Hee)
An official for the King's judicial administration, Min Jung-Ho helps Jang-Geum from time to time. He eventually transfers to the Royal Protectorate, and grows closer to Jang-Geum. Jung-Ho is an educated man with good looks, as well as fine martial arts skills. Struck with admiration for Jang-Geum's wisdom and passion for, he can't help but to fall in love with her.

Choi Keum-Young (Hong Li-Na)
A court lady of the Royal Kitchen, Choi Keum-Young starts her life in the palace as the niece of the influential Lady Choi. Keum-Young is a beauty filled with ambition as well as arrogance. She possesses a lifelong crush on Min Jung-Ho despite their differences in social status, and continually competes with Jang-Geum to become the best cook in the Royal Palace. Through countless conspiracies of the Choi family, Keum-Young eventually has a fateful reunion with Jang-Geum.

King Jungjong (Lim Ho)
The 11th king of the Chosun Dynasty, King Jungjong has a mild but indecisive personality. While executing reformative politics, he meets Jang-Geum and grows to cherish her warm-hearted character and distinguished talents.