Abstract: Objective: To observe the effect of ischemia-reperfusion on the electrophyiology of diaphragm atic muscle in rabbits.Methods: Twelve healthy adult rabbits were randomly divided into experimental and control groups(each of six rabbits).The ischemia-reperfusion injury animal model was produced in rabbits.The diaphragmatic electromyogram(EMGdi) was recorded by computer.The contents of the high/low(H/L) frequency ratio and central frequency(Fc) were detected by Fast Fourier Transform(FFT) at the times of preischemia,post-ischemia and post-reperfusion.Data were analysed by variance analysis and q test.Results: The Fc in experimental group were significantly lower than that of control group(P<0.01) at one hour and two hours after ischemia-reperfusion injury.Conclusions: The electro-activity of diaphragm has been injuried by ischemia-reperfusion.