Abstract: In isolated frog heart and in cat, dog and rabbit heart in situ, the alcoholic extract and glycoside of the seeds of Corchorus acutangulus produced prompt cardiotonic action. The mean lethal doses of this glycoside in cats and guinea pigs were found to be 0.3316 mg/kg±0.0176 (S. E.) and 0.952 mg/kg±0.036 (S. E.), respectively. Furthermore, the following observations for this glycoside in cats were made: (1)The cumulation after 48 hours was only 13.8% of the intravenous dose. (2) By means of slow intrave nous infusion, the critical infusion speed was found to be 0.0064 mg/kg/hr. (3) The enteral absorption was irregular; i. e., after 1, 3, 4 and 5 hours, they were 0～24.1% (mean 15.4%), 0～61% (40.1%), 0～53% (28.5%) and 0～24.5% (8.1%), respectively. (4) Intraportal infusion didn't indicate the importance of the liver in elimination.It was concluded that the pharmacological action of the glycoside of the seeds of Corchorus acutangulus were similar to that of k-Strophanthin.