Abstract: 20μci of ³H--CDCA was given to each normal healthy mouse for study of its absorption, distribution and excretion. Appreciable amount of radioactivity was detected in the blood 15 minutes after administration. Peak value appeared after 6 hours, while a certain level of radioactivity was still detected 12 hours after administration. After continuous administration for three days, the radioactivity in blood could be raised 20 times. Higher radioactivity level was found in bile, intestine and liver. The radioactivity decreased very slowly in intestine.The radioactivity was evidently increased in the intestine, liver and particularly in the bile after continuous administration for three or seven days.Furthermore, repeated administration caused the weight of the bile to increase, the gall bladder was enlarged. Thus it is clear that CDCA has an apparent choleretic action. Within 24 hours after the stomach feeding of ³H—CDCA, the total excretion of radioactivity in feces and urine was 33.9%.