Abstract: Objective To solve the problem that myocardial band of stale hearts treated by formaldehyde cann’t be used for research study. Methods Twenty sheep’s hearts and 20 pig’s hearts were randomly distributed to 3 groups, group 1: fresh pig’s hearts(n=10) and fresh sheep’s hearts (n=10) were dissected by Torrent-Guasp’s method; group 2: pig’s hearts (n=5) and sheep’s hearts (n=5) treated by formaldehyde were dissected by Torrent-Guasp’s method; group 3: pig’s hearts (n=5) and sheep’s hearts (n=5) treated by formaldehyde were dissected by new method. Results All samples in group 1 were successfully unrolled to a myocardial band composed of basal loop and apical loop. The dissecting of samples in group2 were difficult. The root of pulmonary artery and ascending aorta failed to be unfolded because fibrous tissue was tough, right and left fibrous trigone were too firm to be solved by hand. Cardiac muscle fibers couldn’t be stripped along myofibrillar trajectory since they were prone to break because of their friability. On the other hand, being dissected along nature myofibrillar trajectory, all samples in group 3 were successfully unrolled to a myocardial band composed of basal loop and apical loop. Furthermore, myofibrillar trajectory was clear and the exposure of crossing angle between apical ascending segment and descending segment was ideal. Conclusion With Torrent-Guasp’s method, the dissection of myocardial band of hearts was successful in fresh heart, but not in stale heart. On the other hand, with new method, the dissection of myocardial band of hearts was achieved in stale heart group. Our method in this research is a reliable way on dissection of myocardial band in stale hearts treated by formaldehyde.