Two cases of scleredema, in adults, of 20 and 38 years duration are reported. Histochemical studies revealed an increase in acid mucopolysaccharides, probably hyaluronic acid. One case showed an increase in mast cells scattered throughout the entire dermis. Estimation of collagen content, measured as hydroxyproline, revealed about a 505 reduction. Thus, sclerosis is not a feature of scleredema. Moreover, water content was within normal limits. Acid mucopolysaccharides, measured by the hexosamine and uronic acid contents, were increased. Hexoses were normal, thus suggesting no increase in neutral polysaccharides. Noncollagenous proteins, measured as tyrosine, were in normal concentrations.