Various sterols and uncommon fatty acids have been isolated from the three species of Korean marine sponges. Odd-numbered pentadecanoic, heptadecanoic methyl ester and branched 12-methyltetradecanoic, 14-methylpentadecanoic, 15-methylhexadecanoic and 14-methylhexadecanoic methyl ester were isolated along with common tetradecanoic and hexadecanoic methyl ester from Heteropiidae sponge Vosmaeropsis japonica Hozawa collected from Sohuksan island of the Korea sea. Futher elution with more polar solvent gave 5${alpha}$-cholestan-3${eta}$-ol along with minor amount of ergost-25-ene-3${eta}$,5${alpha}$,6${eta}$-triol. On the other hand, marine sponge Hymeniacidon sinapium collected from Yesu Dolsan island of the Korea sea was shown to contain 5${alpha}$-cholestan-3${eta}$-ol, along with minor amount of cholesterol, palmitic, palmitoleic, oleic, stearic, linolenic, and arachidonic acid ethyl ester. Unknown marin sponge collected from the same region was shown to contain large amount of tetradecanoic tetradecyl and hexadecyl ester and cholesteryl acetic and fatty acid ester.