Objective To study the effect of Astragalus on peripheral nerve ischemia reperfusion injury in rabbits.Methods Models of unilateral xciatic nerve ischemia were produced in 40 rabbits.They were randomly divided into 5 groups: control group,ischemia group,reperfusion group,Astragalus-treated group Ⅰand Astragalus-treated group Ⅱ.The changes in the parameters of sciatic nerve were observed.Results With the prolongation of the duration of ischemia and reperfusion,in the ischemia group and reperfusion group,the nerve conductive velocity was slown down to (4.101±0.992) and (5.898± 8.891) m/s,the action potential amptitude decreased to (4.271±1.071) and (2.252±1.527) mV,the latent time prolonged to (1.921±0.204) and (2.393±0.231) ms,the contents of the malondialdehyde (MDA) was increased to (1.29±0.21) and (4.29±0.14) μmol/L and superoxide dismutase (SOD) was declined to (18.93±9.88) and (28.13±9.72) μU/L,respectively ( P <0.05,or P<0.001).As compared with ischemia group by Astragalus-treated group I or with reperfusion group by Astragalus-treated II,the nerve conductive velocity was speeded up <(3.182±0.839) ms,(3.271±1.013) ms>,the action potential amptitude elevated <(1.867±0.512) mV,(2.467±0.219) mV>,the latent time shortened <(1.317±0.324) ms,(2.387±0.175) ms>,SOD activity increased <(10.64±0.79) μU/L,(13.94±0.83) μU/L>,MDA decreased <(1.69±0.01) μmol/L,(1.06±0.20) μmol/L>,respectively (P<0.05 orP<0.001).The pathological changes were alleviated.Conclusion Astragalus has protective effects against ischemia and reperfusion injury of peripheral nerve in rabbits.