The invention discloses a composition for improving the sub-health state of skin and a preparation method thereof. The composition refers to traditional Chinese medicine famous formulas of 'decoction of four mild drugs' and 'decoction of four drugs', and takes Chinese angelica, bighead atractylodes rhizome, white paeony root, white poria, ligusticum chuanxiong hort, honey-fried licorice root and donkey-hide gelatin as main components; various skin-benefiting nutritional ingredients such as the linseed oil, the collagen oligopeptide powder, the vitamin C, thefructus corni extract, the hyaluronic acid and the glucose are supplemented, so that the effects of invigorating the spleen, replenishing qi, replenishing blood and regulating blood are achieved. Mouse tests prove that by using the composition, the moisture content in mouse skin can be effectively kept, the skin elasticity is increased, no stress response exists, and the effect of improving skin sub-health states such as dark yellow skin color, rough skin and lack of elasticity can be achieved. Besides, the composition is prepared by adopting a special method, effective components in the raw materials are fully extracted and reserved, so that the functions of the components are more stable, and the composition is easy to carry and convenient to use.