King Jeonggan (1021–1069; born Wang Gi) was a Goryeo Royal Prince as the 5th son of King Hyeonjong, from Queen Wonhye. He was a brother to King Munjong and Queen Hyosa, also became both of paternal uncle and father-in-law to King Sunjong. He was known as Duke Pyeongyang and Duke of the Gaeseong State during his lifetime.