Jeong Yak-jong was a Korean civilian official and Catholic martyr born in 1760 in Gwangju. Following his conversion by the priest Chou Wen-Mu, he became a significant figure in the early spread of the Catholic faith within the Joseon dynasty. He is notably the father of Paul Chong Hasang and the brother of Chŏng Yagyong. His efforts to communicate religious teachings to the general public through the use of Hangul helped establish a foundation for the local church.