Background: The cardiovascular system is significantly agitated by loss of gravity. In microgravity, the body fluids shift toward the thoracic cavity, induced the heart becomes more spherical. This further increased the cardiac preload with an increasing of transmural central venous pressure, affects the right heart ventricles to tolerating the enhanced preload on the right ventricular wall. Method: In this study we investigated the rat right ventricle remodeling in simulating persistent microgravity by using tail-suspension model, examined the remolding of the heart and the specific STAT3 expression in right heart myocardium. Result: The results indicated that microgravity induced heart remodeling included a significant increasing of the ventricular weight in the left. However, the right ventricle was not increased significantly in the microgravity simulation rats. The histological study demonstrated that the outstanding development on right ventricular wall which included the gap junction remodeling and STAT3 signaling protein specific accumulation in the right ventricles. Conclusion: The results existed that the right cardiac ventricle has a distinctive remodeling process during microgravity simulation which was not the muscular hypertrophy and relative weight increasing, but manifested the STAT3 accumulation and the electrical gap junction remodeling. The effect of microgravity induced right ventricle remodeling and the STAT3 specific accumulation can be used for multi-purpose research. Key words: Microgravity simulation; Right ventricle remodeling; Intercalated disc