The invention discloses a plant composition for improving keratosis pilaris as well as a preparation method and applications of the plant composition. The plant composition is prepared by extracting the following raw materials in parts by weight: 35-45 parts of fructus kochiae, 35-45 parts of gerbera herb, 35-45 parts of radix zanthoxyli, 20-30 parts of roots of Chinese barberry, and 15-25 parts of apricot kernels. The plant composition has the efficacies of removing aged keratin, regulating the normal metabolism of the skin, diminishing inflammation and removing red and swollen affected parts, and inhibiting pruritus. The plant composition is added into cosmetics for use, and a process is simple. The experiments prove that the cosmetics containing the plant composition can effectively improve the relevant symptoms caused by keratosis pilaris, and enable the skin to be smooth and white.