Ｏｂｊｅｃｔｉｖｅ　To investigate the effect of propofol on mitochondrial ultrastructure and mitochondrial fission during oxygen-glucose deprivation and reperfusion injury in hippocampal neurons of rats.　Methods　Cultured primary hippocampal cells were subjected to oxygen-glucose deprivation for 6 h, followed by 20 h of reperfusion and then were randomly divided into 6 groups(n=6): control group (group C), vehicle group (group V), group ischemia/reperfusion(I/R), I/R+propofol(P1, P10, P50) treatment groups, propofol 1, 10, 50 μmol/L were added during oxygen-glucose deprivation and reperfusion period. Mitochondrial ultrastructure(using a transmission electron microscop), fluorescence intensity of mitochondria and quantitative colocalization of Drp1 and Fis1(using a laser scanning confocal microscope), expression of Drp1 and Fis1(by Western blot) were measured.　Results　Compared with group C, mitochondrial ultrastructure were destroyed and fluorescence intensity of mitochondria(0.079±0.032) and quantitative colocalization of Drp1 and Fis1(0.815±0.048), the expression of Drp1(0.756±0.082) and Fis1(1.164±0.070) were increased in other groups (P<0.05). Compared with group I/R, mitochondrial ultrastructure were improve（P<0.05） and fluorescence intensity of mitochondria(0.065±0.010, 0.056±0.011, 0.070±0.024)(P<0.05) and quantitative colocalization of Drp1 and Fis1(0.649±0.015, 0.627±0.008, 0.702±0.029), the expression of Drp1(0.627±0.005, 0.322±0.009, 0.696±0.007) and Fis1(0.773±0.012, 0.670±0.022, 0.796±0.016) were decreased in P1, P10 and P50 groups (P<0.05).　Conclusions　Propofol 1, 10, 50 μmol/L could inhibit I/R-induced mitochondrial fission by suppressing the expression and the binding of Drp1 and Fis1, of which 10 μmol/L was the optimal dose in hippocampal neurons of rats.