Skin collagen of six discarded fish species was analyzed and compared. Acid soluble collagen (ASC) was extracted; a characteristic sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profile for type I collagen was obtained, except for Chimaera mostrosa. Contents of collagen calculated from HPro (31.85% average) were higher than those determined from ASC extracts (17.75% average), with Galeus spp. being the species with the higher percentage. Amino acid analysis revealed the typical composition of collagen, with very few differences among species. Specific profiles were obtained after protease digestion. Denaturation temperature of ASC correlated well with imino and hydroxyproline contents.Results demonstrate the feasibility of using the obtained collagens in different industrial applications.