Abstract: A tincture was prepared from Erysimum cheiranthoides L. that grew wild in the Northeast of China and, after alcohol was removed by vaporization, was suspended in saline solution of suitable concentration; it was then used in experiments. Through repeated experiments on hearts (of frogs and rabbits) in situ, on perfused isolated hearts (of frogs and rabbits) and on ECG (cats), it was found that the preparation had a cardiotonic effect and, in addition to the cardiac effect, it displayed a positive glucoside reaction as well. Judging from the fact that the active principles of the other species of the same plant were generally cardiac glucosides, it must, the authors believed, contain cardiac glucoside. The effect of the preparation was very rapid; the "log dose-response (percentage of death in probits) line" was parallel to that of k-Strophanthin; and it had no cumulative effect. Hence the authors concluded that its cardiac actions were similar to those of k-Strophanthin. One gram of the dry powder made of the aerial part of the plant was approximately equal in potency to 2.91 mg k-Strophanthin. The mouse LD₅₀ (24 hr., i.p.) is 5.24±0.48gm/kg (P=0.95).