Objective To observe myocardial cell apoptosis and Caspase-3 protein expression of myocardial infarction area after acute myocardial infarction (AMI) and explore the mechanisms of myocardial cell apoptosis after AMI.Methods 8 pigs were treated with coronary angiography and obtuse gelatin sponge closure. 1 pig was only treated with coronary angiography as control. The other 7 pigs were executed at 1d, 3d, 5d, 7d, 10d, 14d and 28d. The apoptosis and Caspase-3 protein expression of myocardial infarction area were detected.Results The AI of control and the pig executed at 1d, 3d, 5d, 7d, 10d, 14d and 28d were (2.1±1.0)%, (67.8±4.3)%, (43.6±5.7)%, (39.5±4.2)%, (38.3±7.4)%, (26.7±3.5)%, (19.8±6.2)% and (18.6±5.4)%. The expression density of Caspase-3 of control and the pig executed at 1d, 3d, 5d, 7d, 10d, 14d and 28d were 36%, 788%, 58.2%, 56.3%, 54.5%, 49.6%, 34.6% and 32.1%.Conclusion After AMI, myocardial infarction and ischemia area present a large number of apoptotic factors caspase-3 protein. Acute ischemia during myocardial hypoxia stimulation accelerates the induction of the launch of the myocardial cell apoptosis, apoptosis occurs. The myocardial remodeling, myocardial fibrosis and myocardial systolic function change are closely related to the cardiac structure and function.