Abstract: Objective To determine the effect of koumine parenteral solution on the ne rvous, respiratory and cardiovascular systems of experimental animals.Methods Mouse spontaneous activities under the influence of the koumine injection were recorded with a photoelectric counter, and canine femoral artery pressure was de termined by CYS-0.5 pressure transducer, respiratory curve described with TB-61 1 tension transducer and electrocardiogram (ECG) recorded with subcutaneous elec -trodes in the extremities after the injection. The above indices were automatic ally sampled and processed by multifunctional signal processor after being inpu tt to a computer. In this experiment, we observed the changes in the general beh avior of the mice and their spontaneous activities within 15min, along with th e heart rate, maximum, minimum, and mean value of car-diac electric voltage, mea n arterial pressure, respiratory rate and respiratory depth of the dogs before a nd at 10, 20, 30, 60, 90, 120 min after koumine injection.Results Koumine injec tion significantly decreased mouse spontaneous activities in moderate and high- dose groups, but did not produce obvious effect on the respiratory system, mean arterial pressure, and maximum, minimum, and mean values of cardiac electric vo ltage in dogs. The heart rate of the dogs did not undergo obvious changes in re sponse to the injection at a low dose, but median and high doses of the injectio n produced obvious effects.Conclusion Koumine injection has definite sedative e ffect in mice, and does not affect the respiratory and cardiovascular systems of dogs with the exception of the heart rate.