Lady Jang Hui-bin (?-1701) is one of the best known royal concubines of the Joseon Dynasty.
She was the daughter of Jang Hyeong (Hangul: 장형, Hanja: 張炯) and Lady Yun of the Papyeong Yun clan, her personal name was Jang Ok-jeong (Hangul: 장옥정, Hanja: 張玉貞).
Ok-jeong became a lady-in-waiting to Queen Dowager Jangnyeol (King Injo's second queen) at the recommendation of Prince Dongpyeong (King Sukjong's first cousin once removed). In 1686, after a visit with his step-great-grandmother (Queen Dowager Jangryeol), King Sukjong saw her and made her his concubine with the title of suk-won. In 1688, she was elevatedto so-ui, and in 1688 was elevated to the rank of hui-bin after giving birth to a son (the future King Gyeongjong). She possibly had a second son, Prince Seongsu, but his identity is disputed. When Queen Inhyeon was deposed & forced into exile in May 1688, Jang hui-bin became Sukjong's third Queen Consort, backed by the Soron faction. Her son was made the Crown Prince.
Later, in 1694, with the reinstatement of Queen Inhyeon, Jang was demoted back to hui-bin. In 1701, Queen Inhyeon died of an unknown disease.