Abstract: AIM To exlpore the role of pericytes during the generation and the development of myocardial fibrosis. METHODS After pericytes were double-labeled with immunofluorescence, the changes of the number of pericytes in the early myocardial ischemia necrosis was observed under laser scanning confocal microscopy. RESULTS Observation under laser scanning confocal microscope demonstrated the number of pericytes around endothelial cells increased significantly 4 hours after injection of Isp, descended 12 hours after the injection, and the number of pericytes was markedly lower than the normal level 48 hours after the injection (P<0.05). CONCLUSION Pericytes as myocardial interstitial cells may be the main effector cells in the generation and development of myocardial fibrosis.