This study was designed to elucidate the lipid contents, neutral lipids components and fatty acid composition in fresh shellfishes, produced in Korea. Four kinds of shellfishes including sea mussel, short-necked clam, corb shell and and ark shell were selected according to the higher sales order and cheaper retail price at fish markets in Seoul in July 1985. The results abtained were as follows; 1. The average total lipid contents in four shellfishes were 2.3% by wet weight basis. The ratios of neutrial lipid, glycolipid and phospholipid in the total lipid were 51.1 : 4.9 : 44.0 in sea mussel, 66.0 : 3.2 : 30.8 in ark shell, 37.8 : 2.2 : 60.0 in short-necked clam and 54.5 : 2.0 : 53.5 in corb shell, 2. The average value of acid value, iodine value and unsaponifiables contents of total lipids were 1.3, 217.8, 92.0 and 20.3%, respectively. 3. The composition of the neutral lipids were triglycerides, esterified fatty acids, sterylesters, free sterols and monoglycerides in four shellfishes. 4. The major fatty acid composition of total lipids were palmitic, eicosapentaenoic, docosahexaenoic and palmitoleic acids in four shellfishes. The average total unsaturated fatty acids of total lipid were 64.5%, and $omega$-3 highly unsaturated fatty acids were 27.0%. The average p/s Ratiio were 1.3.