Iryeon 一然 (Korean reading; Sino-Korean: Iryeon; standard Mandarin: Yīrán; 1206–1289), birth name Kim Gyeonmyeong 金見明, with the religious name Hoeyeon 晦然 in his early career, was a major Goryeo 高麗 Sŏn 禪 master and the compiler of the Samguk yusa 三國遺事 (KR6r0016). He was born in Gyeongju 慶州 and tonsured at age nine; he passed the Sŏn monastic examination in 1227 and rose through the Goryeo Buddhist establishment over the following decades. In 1259 he was appointed Daeseonsa 大禪師 (“Great Sŏn Master”), and in 1283, late in life, he was elevated to Wangsa 王師 (“Royal Preceptor”) under King Chungyŏl 忠烈王. He retired to Ingaksa 麟角寺 monastery, where he died in 1289 with the posthumous title Bogak Guksa 普覺國尊 (“National Preceptor of Universal Awakening”).
The Samguk yusa, compiled in the early 1280s and possibly finalised by his disciple Mugŭk 無極 after his death, is his sole surviving major work and the principal vehicle for his name in subsequent Korean cultural memory. It supplies, alongside its Buddhist hagiographical material, the earliest extant version of the 檀君 foundation myth and fourteen Hyangga 鄉歌 vernacular poems, making the work a national-historical landmark as well as a Buddhist text.
He left a substantial body of commentarial and Sŏn writings, of which only the Samguk yusa and a few minor pieces survive in full.