The story takes place Korea, during the Joseon dynasty. After her father and mother get killed, Jang Geum is left on her own. She enters the palace and learns that she has extraordinary gifts of cooking and learning. She grows up and eventually runs into trouble. Through many trials she perseveres, and becomes the best female doctor Korea has ever seen.
One similarity is the both female leads in both dramas are born as a commoner. They enter the palace with the servant status but catches the King's attention. The one thing is that in daejanggeum, the female lead rejects the kings love. While in Dongi, she marries the king. Both are historical, life, roamce, family dramas. One strong thing that ties these two dramas together is that there is someone behind them, pulling strings to try to destroy them.