The invention relates to the technical field of cosmetics, and especially relates to a cosmetic containing spider silk hydrolysate. The cosmetic comprises the spider silk hydrolysate, and the spider silk hydrolysate is prepared by the following steps: spider silk is crushed, crushed spider silk and a sodium hydroxide solution are mixed, hydrolysis is carried out at 80-90 DEG C for 4-5 hours, centrifugation is carried out, and hydrolysate is obtained; pH value of the hydrolysate is adjusted to 4.0-5.5, the hydrolysate is filtered with a 200nm membrane, and the spider silk hydrolysate is obtained. The hydrolysis yield of amino acids is higher than 70%, and the amount of micro-molecule polypeptides is 72% or above; in the hydrolysate, methionine is not detected, except phenylalanine and tyrosine, yield of other amino acids is higher than 60%. The spider silk hydrolysate is used for masks for beauty treatment and skin care, beauty treatment characteristics of spider silk for water supplement, moisture retention, tightness, crease resistance, inflammation resistance, repair and the like are fully performed, the product characteristics are distinct, efficacy is substantial, and beauty treatment demands of people are satisfied.