1. Total AsA levels in blood were determined in 111 female subjects using dinitrophenyl hydrazine (DNP) method. The values were 0.2-1.4mg/100ml, averaging 0.76mg/100ml.2. Urinary excretions of AsA of these subjects had a definite correlation with the blood levels. The urinary excretions, however, sometimes abnormally increased when the blood levels exceeded 1mg/100ml.3. Blood AsA levels showed maximum values (1.16-1.36mg/100ml) following successive oral administration of 300mg of ascorbic acid for 3-5 days. These values showed individual differences.4. The rise of blood levels after administration of the vitamin was rapid in the case of a subcutaneous injection, but slow in the case of oral administration. The urinary excretions showed the maximum values after 1, 1-2, and 4 hours respectively following intravenous, subcutaneous and oral administrations and the excretion ratios after arriving the saturation state were about 70, 50-90, and 45 per cent, respectively.5. The ratios of urinary excretion after loading with the vitamin were directly proportional to the blood levels of the vitamin. The AsA values obtained by DNP method are therefore considered to be suitable for expressing the nutritional state of vitamin C.