Choe Sejin (Korean: 최세진; Hanja: 崔世珍, [t͡ɕʰwe̞ sʰed͡ʑin]; 1465 – February 10, 1542) was a Korean linguist, and a translator and interpreter of the Chinese language during the Joseon Dynasty. He is of the Goesan Choe clan and his courtesy name was Gongseo (공서; 公瑞). He is widely known for his research with the Korean hangul letters, and comparative studies with Chinese and Korean, which further led to the propagation of hangul during a time period when Chinese characters were used as the main system of writing. Choe was recognized by many for his talents as an official interpreter in the Korean Embassies in Beijing and in his works in hangul research. However, he lived a tumultuous life due to this middle class status, which led him to be the target of many envious aristocrats of his era.