In 1946, Acatalasemia was discovered by S. Takahara. A case of Acatalasemia was reported. Patient was 3year-old boy and chief complaint was frequent fever up, his clinical diagnosises were hypertrophy of the faucial and pharyngeal tonsil. During the operation, its wound was washed with hydrogen peroxide, in a moment, the blood covered with its wound became blackend. In our case, this boy's parents did not have a blood relationship. And since now, this boy did not have stomatitis so called Takahara's disease. Further, we performed Heinz body formation test. Such acatalasemic patients should be protected from oxidative challenge by oxidative drugs or infections.