To understand the changes of collagen contents and composition in tissues sampls of hypertrophic scar and keloid.The total contents of type Ⅰ/Ⅲ collagen were reflected from estimation of hydroxyproline (pro). The proα1(Ⅰ) and proα1(Ⅲ) collagen chains were separated by SDS-PAGE, then their polypeptides were visualized by staining with Coomassie Brilliant Blue and the ratio of collagen Ⅰ/Ⅲ was calculated with the help of computer color image analysis system.The total contents of collagen in tissues of hypertrophic scar and keloid were very close (0.988±0.141 vs. 1.10±0.159 mmol/L, respectively), all higher than those in tissues of normal scar and healthy skin ; while the ratio of collagen Ⅰ/Ⅲ in keloid tissues was 11.491±1.223, higher than those in hypertrophic scar, normal scar and healthy skin ; whereas that in tissues of hypertrophic scar was more or less similar to those of normal scar and healthy skin.[Conclusion]Keloid and hypertrophic scar tissues display various expression intensity of different types of collagen.This result possesses certain potential significance for pathogenesis elucidation of hypertrophic scarring and keloid as well as differentiation between these two diseases process.