Some sea urchins were collected from the subtidal rocky bottom of Munseom near Seogwipo, Jejudo Island by SCUBA diving from April to May, 2008 and identified on the basis of their morphological characteristics. Among them, Tripneustes gratilla (Linnaeus, 1758) of Family Toxopneustidae was newly recorded from Korea and redescribed on the specimen collected at a depth of 25 m between Munseom and Sekkiseom. The detailed morphological description was presented with the photographs. This species was characterized by the very naked median areas of ambulacral and interambulacral portions and this genus was the first record in Korea. Eighteen echinoids are so far recorded in Jejudo Island, Korea.