BACKGROUND:Yeasts are used in a variety of industries. However,most industries are biased toward Saccharomyces cerevisiae ; so we sought to explore non-conventional yeasts (NCY). This study aimed to isolate yeasts from seawater collected from the East Sea of Korea and to analyze the NCY. METHODS AND RESULTS:We first collected seawater and performed pure isolation using four kinds of medium (GPY, DOB+CSM,DG18, and SCG). In total, 314 strains and 17 genera were isolated by ITS sequencing, including Aureobasidium pullulans (236 strains), Cryptococcus (19 strains), Cystobasidium (18 strains), and Rhodotorula (9 strains). Upon in-depth analysis, A. pullulans, the most dominant genus (236 strains), was divided into Group II (147 strains), Unknown I (8 strains), and Unknown II (49 strains). CONCLUSION: In this study, a total of 314 strains were isolated from seawater; many of these yeasts have been found and reported in seawater previously. In-depth analysis of A. pullulans, showed the dominance of Group I (21 strains) and Group II (147 strains).We also discovered Unknown I (8 strains) and Unknown II (49 strains), which have not been reported previously.