Abstract: In normal dogs intragastric administration of the decoction of the leaves of C.trichdtomum induced emesis after a single dose of 20g(crude drug)/kg or more,but no emesis below 10g/kg. Daily administration of 10g/kg for 3 weeks rendered no significant changes in the liver function, blood picture,EKG,and pathologic examination. Five Goldblatt renal hypertensive dogs were used for the experimental therapy.Blood pres- sure was measured by auscultation on the carotid loop.C.trichotomum was given 10g/kg/day for 4 weeks.Hypotension began in the 2nd week,and became more marked on further medication. The weekly average diastolic pressure decreased 32,17,6,20,and 12 mm Hg(25%,14%,5%, 16%,and 10%) respectively.The liver function and the blood picture were apparendy unaltered. After 3 weeks of medication the T wave in the EKG was found to be inverted in 3 dogs. When compared with the therapeutic activities of the Chinese drugs previously tested on the hypertensive dogs in this laboratory,C.trichotomum is probably less effective than Veratrum Schindleri,Scutellaria baicalcnesis,and the total alkaloids from Rauwolfia wrticillata,is similar to the Compositus Erxian-heji,but is better than Eucommia ulmoides.