Objective To observe the pathological changes of heart failure caused by transverse aortic constriction in rats. Methods Partial thoracotomy was performed to the second rib and the transverse aortic constriction was performed between the innominate and left carotid arteries to establish a model of heart failure in 24 rats. The same operation was performed on another 8 rats, except for the ligation of the transverse aorta. Echocardiographic assessment, hemodynamic measurement, myocardial histopathological examination and NT-proBNP measurement were performed to the sham group at 12 weeks and model group at 4 weeks, 8 weeks, 12 weeks after the operation. Result At 4 weeks after the operation, NT-proBNP, EF, FS and -dp/dtmax of the model group was significantly increased and LVESV, +dp/dtmax of the model group were significantly decreased (P<0.05). At 8 weeks after the operation, EF and-dp/dtmax of the model group were increased and +dp/dtmax of the model group was significantly decreased (P<0.05). At 12 weeks after the operation, NT-proBNP, EF and +dp/dtmax of the model group were decreased, and LVESV, LVEDV and -dp/dtmax of the model group were increased (P<0.05). The cardiomyocytes became hypertrophic and lined up in disorder at 4 weeks after the operation. Pathologic examination of the myocardial tissue showed connective tissue proliferation and inflammatory cell infiltration at 8 weeks after the operation, and cardiomyocyte apoptosis and collagen fiber deposition at 12 weeks after the operation. Conclusions Transverse aortic constriction induces heart failure in rats. The pathological processes are compensatory hypertrophy at 4 weeks after the operation, initial reaction of decompensation at 8 weeks after the operation, and heart failure at 12 weeks after the operation.