The order Prorocentales currently includes two genera Prorocentrum Ehrenberg and Mesoporos Lillick. The Prorocentrum genus is a predominant group throughout the year found in Korean waters. To date, the Prorocentrum genus includes 31 species and the Mesoporos genus has only one species in Korean waters. In this study, we identified one Mesoporos species and three Prorocentrum species around a coast of Jeju Island, and described them as newly recorded species in Korean waters.