Sin Gwang-su (Korean: 신광수; Hanja: 申光洙; 1712–1775) was a poet of the late Joseon Dynasty. Living in the time of King Yeongjo, he was unable to attain a position of rank because his family was aligned with the Southerners faction. He married the daughter of Yun Duseo and became associated with Silhak. At 39, Sin finally passed the higher exam of the gwageo and was sent to Jeju as an official. He wrote a description of the island. His famed words from later life include the Gwan sang yung ma (관산융마; 關山戎馬) and Gwanseo akbu (관서악부; 關西樂府).