PROBLEM TO BE SOLVED: To provide a new component or a protective agent for stratum corneum peeling enzymes which can protect a protease involved in the adjustment of turnover of the skin from drying to prevent the deterioration of its activity, can recover the inherent activity of the protease whose activity has been deteriorated, and excels in an effect of preventing and improving chapped skin due to drying.SOLUTION: A sericin-derived polypeptide includes 10-20 mol% basic amino acid as an amino acid composition and has a weight-average molecular weight of 1,000-70,000 and absorbance of a 0.5 wt.% solution thereof at 600 nm in the pH range of 2.5-8.0 of not greater than 0.2. The protective agent for stratum corneum peeling enzymes has this polypeptide as an active ingredient.