Attitude of the liver toward intravenous administration of vitamin A was examined with dogs, using a liver catheter. Vitamin A value of blood of hepatic vein was always lower than that of the artery after the administration, while inflow of the vitamin into the liver was observed. But during two hours thereafter, either vitamin A in the blood of hepatic vein or that of hepatic artery showed a high level one after another. This suggests that the deposion of vitamin A in the liver might be difficult in a nutritional sense. In the animals receiving a relatively small amount of vitamin A, the retention of vitamin A in the liver seems to be easier. After the administration of 20,000 to 100,000 IU of vitamin A for dogs, the excretion of the vitamin into bile was not observed.