A self-emulsifying composition which comprises at least one compound selected from the group consisting of an .omega.3 polyhydric unsaturated fatty acid and a pharmaceutically acceptable salt and an ester thereof in the total amount of 50 to 95% by mass and an emulsifying agent having a hydrophilic-lipophilic balance of 10 or more in an amount of 5 to 50% by mass, does not need the addition of ethanol or needs the addition of ethanol at a low concentration, has excellent self-emulsifying properties, excellent composition dispersibility, excellent emulsion stability and excellent absorbability, and can be used for medical purposes.
