Provided are a stabilized, skin-whitening and antioxidative cosmetic composition including resveratrol as a main component and either a primary stabilizer selected from cyclodextrin, polyethyleneglycol, and a mixture thereof, or a combination of the primary stabilizer and a secondary stabilizer selected from an alpha-lipoic acid, a water-soluble whitening composition, a phellodendron extract, an alteromonas ferment extract, and a mixture thereof, and a method for preparing the same. The cosmetic composition provides excellent skin whitening and antioxidative effects for a long-term even when used in a small quantity. Furthermore, solubility of the resveratrol and the alpha-lipoic acid in polyol or ethanol is enhanced, thereby improving low use satisfaction and skin irritation that may be caused due to excess use of an organic solvent. In addition, problems such as crystal precipitation at low temperature, off-flavor and discoloration upon exposure to sun light can be solved.