1) If inject serum of this disease in rabbits, in every cases where injected once, as well as 7-times-continued case, haemoglobin, erylhrocytes, as well as platelet indicate a marked decrease. 2) No anemia-producing substance will be seen in serum either of healthy person or of posthemorrhagic anemic patient. 3) Those anemia producing substances found in the patient of this disease proved soluble both for alcohol as well as ether. 4) These substances exist in acid fraction. 5) These substances have the thermostable character for the 30 minutes heating of 100°C.