glycogenosis type Ⅳ, which is characterized by deposits of polysaccharide in the liver and liver cirrhosis resembling postencratic type, were described in two children. They were siblings, had a sister with an identical disease and had unrelated parents. Furthermore, in one case in which a partial autopsy was performed, two kind of the polysaccharide were noted in the cardiac muscle, skeletal muscle, smooth muscle and reticuloendothelial cells. The one was normal glycogen and the other was not identical with normal glycogen because of its diastase resistance. The genesis of the cirrhosis may have been a reaction to the stimulation by the polysaccharide as a foreign body.