The present invention relates to a feed additive for improving pig skin color and hair of pigs and a preparation method thereof and an application thereof, and belongs to the field of feeds. The feedadditive for improving the pig skin color and hair of the pigs comprises astaxanthin, porous zinc oxide, tea polyphenols, compound amino acids, multivitamins, and Chinese herbal medicines. The feed additive is rich in the astaxanthin and can effectively improve the skin color and hair conditions of the pigs. The preparation method comprises the following steps: the Chinese herbal medicines are crushed, and the crushed Chinese herbal medicines are then mixed with the astaxanthin, porous zinc oxide, tea polyphenols, compound amino acids and multivitamins in ratios; and the astaxanthin is obtained by compounded enzyme enzymatic hydrolysis of phaffia rhodozyma and drying the hydrolyzed product. The preparation method is simple in operations, can effectively release the astaxanthin contained inthe phaffia rhodozyma and is beneficial to increase a utilization rate of the astaxanthin. The feed additive is used for preparing feed for the pigs, can effectively improve skin color and hair quality of the pigs, and at the same time can also significantly increases daily feed intake and daily weight gain of the pigs.