Objective To investigate the histological changes of the right ventricular remodeling in Xinjiang Marmota baibacina which are adapted to high-altitude hypoxia. Methods Hematoxylin and eosin and Masson staining was used to examine the pathological changes and degree of fibrosis, and immunohistochemical technique was used to detect connexin 43 (CX43)expression in the right ventricular myocardium. Results In the right ventricular myocardium, cardiomyocyte hypertrophy and increased amount of collagen fibers were observed. The right ventricular hypertrophy index and weight index of Marmota baibacina were significantly higher, and expression of CX43 was significantly reduced than that of normal rats (P<0.05 for both). Conclusions High-altitude hypoxia induces right ventricular remodeling in Xinjiang Marmota baibacina. It can be used as an ideal animal model for studies on the mechanisms of hypoxia adaptation on high-altitude plateau.