Observing leukocyte motility and leukocyte phagocytosis of Indiaink on the infectious hepatitis cases, and the following results were obtained. 1. In the healthy individuals, the leukocyte motility was ranging over 22.05 to 35.71 μ/min. and 1.88 to 2.22 in the leukocyte phagocytosis of India-ink. 2. In the acute hepatitis cases, the leukocyte motility was depressed initially and was then accelated in the convalescent stadium. Leukocyte phagocytosis of India-ink showed similar tendencies although they were fairly variable in the clinical courses. 3. The both functions of leukocyte showed approximate correlations to the impairments of liver functions. 4. In the acute hepatitis cases, the both functions of leukocyte were depressed in almost parallel with fever and leukocytosis. 5. In the chronic hepatitis cases, the leukocyte motility was within normal range, however, the phagocytosis of India-ink was depressed in some cases. The leukocyte motility showed approximate correlation to the impairments of liver function, on the other hand, the phagocytosis of India-ink did not always showed such correlation.