A skin external preparation includes at least arginine, aspartic acid, isoleucine, leucine, lysine, threonine, glycine, histidine, serine, valine, tyrosine, cysteine, phenylalanine, hydroxyproline and acylglutamine among amino acids, or salts thereof, and a skin external preparation includes: at least arginine, aspartic acid, isoleucine, leucine, lysine and threonine among amino acids, or salts thereof, and a hydrolyzed silk.