She is a beautiful and intelligent girl with a positive attitude. She's haunted by many series of trouble and difficulties yet she overcomes them with the iron-strong will. One day a rebellion breaks out and this brings her separation from her father and even her mother's death. She enters the royal palace at the age of ten and she puts her heart and soul, finally becoming the best royal cook of her times. One day she falls into a conspiracy and is kicked out from the palace becoming a maidservant. But she doesn't stop here. She studies medicines and re-enters the palace, ultimately becoming the supreme royal physician and also becoming the first woman physician in history to serve the king.
While he was working at a city hall, he encounters Jang-Geum and helps her get a golden pheasant. And this puts him a serious trouble where he even risks his own life. He's an outstanding scholar who combines both learning and the martial arts. He is a learned man with both good looks and high intelligence. He is left a widower soon after marriage, and volunteers to be on night duty which naturally brings him close to Jang-Geum. Admiring Jang-Geum's wisdom and passion for learning, he helps her in many ways and falls in love with her. But his love for Jang-Geum also puts him in a lot of trouble.
She enters the royal palace with Jang-Geum and becomes her long-time rival. She is an arrogant girl burning with ambitions and uses her beauty as a bait. Despite the disparity in social standing, ever since she was little, she has loved Jung-Ho but her love is never returned. She competes with Jang-Geum to become the best royal cook.
He is the 11th king of Chosun Dynasty. He is a very gentle man but extremely irresolute and indecisive. He tries to reform the political system and meets Jang-Geum. He cherishes her warm-hearted nature and many talents. He later loves jang-Geum not as his physician but as a woman.