Summary A study of the hexose hexosamine, sialic acid, uronic acid, glycogen, and collagen fractions has been made on hypertrophic scars, nonhypertrophic scars, and normal skin. Hexose, hexosamine, sialic acid, uronic acid, and glycogen levels were significantly and consistently elevated in hypertrophic scars. These same components were slightly, but significantly, higher in the nonhypertrophic scars. Salt-soluble collagen of hypertrophic scars was significantly elevated, citrate-soluble and insoluble collagen fractions were not different in the three groups. From these data it is concluded that hypertrophic scars contain more glycoprotein and mucopolysaccharide and are more active metabolically.