A soft capsule preparation which comprises a dispersion of (2E,4E,6E,10E)-3,7,11,15-tetramethyl-2,4,6,10,14-hexadecapentaenoic acid in a vegetable oil filled in a soft capsule comprising a shell having a light blocking effect. The soft capsule preparation preferably comprises polyoxyethylene sorbitan monooleate and glycerol monostearate and the like as surfactants. As the vegetable oil, soybean oil, sesame oil, a mixture thereof, or the like may be used.