Abstract： Objective To investigate the microstructure and ultrastructure changes of cardiac muscle, pallium, lung, liver and kidney tissue and hemodynamic effects after the success of cardiac arrest (CA)-cardiopulmonary resuscitation(CPR) of swine. Method A total of 16 Beijing swine(weight 29 ～ 35 kg)were randomly (random number) divided into normal-control group ( n = 8) and standard CPR group ( n = 8). The swine of the former group were only given anesthetized and intubated, without ventricular fibrillation and CPR. The swine of the latter group were given standard CPR after 4 min of untreated VF, from 10 min after restoration of spontaneous cirkg) and keep for 6 h. And cardiac output (CO), left ventricular maximal rate of systolic pressure ( + dp/dtmax),maximum reduction of left ventricular diastolic velocity ( - dp/dtmax), heart rate (HR) and mean arterial pressure (MAP) of these animals before ventricular fibrillation and 0.5 h, 2 h, 4 h, 6 h after ROSC have been monitored.All swine were put to death after 6 h,and got their cardiac apex, pallium, left lung, right lobe of liver and upper pole of left kidney quickly for microstructure and ultrastructure studies. Statistical analysis was performed using two paired samples t test. Results At different time points after restoration of spontaneous circulation, the cardiac output (CO),left ventricular maximal rate of systolic pressure ( + dp/dtmax), maximum reduction of left ventricular diastolic velocity (- dp/dtmax) were significantly lower than before ventricular fibrillation, with significant difference ( P ＜ 0.05). And HR of different time points were increased significantly ( P ＜ 0.05), with no significantly difference between MAP of each time points ( P ＞ 0.05). Compared with the normal-control group, the cardiac muscle, pallium, lung, liver and kidney tissue of the swine in standard CPR group were found different degree of damages in their microstructure and ultrastructure sections. The damages of the cardiac muscle, pallium, and lung tissue were more obviously. Conclusions Sudden cardiac arrest(CA)-cardiopulmonary resuscitation(CPR) could cause different degree of damages and hemodynamic effects on the body, through our ROSC 6 h model, the damages of the cardiac muscle, pallium and lung were more severity, the damages of liver and kidney were lighter.