The present invention relates to a skin-improving cosmetic composition containing a fusion protein to which a skin permeation-promoting peptide is bound. More specifically, the present invention relates to a fusion protein to which PDGFa is bound to a skin-permeation-promoting peptide. The present invention relates to a skin improving cosmetic composition containing the fusion protein, a skin improving functional cosmetic, a hair loss improving cosmetic composition, and a non-pharmaceutical product composition containing the fusion protein.本発明は、皮膚透過促進用ペプチドが結合された融合タンパク質を含む皮膚改善用化粧料組成物に関し、より具体的には、本発明は、皮膚透過促進用ペプチドにPDGFaが結合された融合タンパク質、上記融合タンパク質を含む皮膚改善用化粧料組成物、皮膚改善用機能性化粧品、脱毛改善用化粧料組成物及び前記融合タンパク質を含む医薬部外品組成物に関する。