［］This study establishes a rat model of venous thrombosis in a plateau hypobaric hypoxic environment and investigates the effect of this environment on venous thrombosis. Methods: A total of 144 healthy male SD rats were randomly assigned to four groups, with 36 rats in each group. The groups included the plain sham operation group (Group A, n=36), the plain operation group (Group B, n=36), the plateau altitude 6000m + sham operation group (Group C, n=36), and the plateau altitude 6000m surgery group (Group D, n=36). Groups A and B were maintained in a plain normoxic environment, while groups C and D were subjected to a plateau environment. In the surgical groups, a method of "quantitative constriction" was employed to incompletely obstruct the inferior vena cava blood flow. Each group was further divided into subgroups based on time points: 1 day, 3 days, 5 days, 7 days, 14 days, and 21 days (n=6). Regular vascular ultrasound monitoring was conducted, and blood samples were taken for whole blood viscosity testing and the assessment of inflammatory indicators, including ET-1, TAT, and IL-6. Coagulation function was evaluated through APTT, PT, D-dimer, and TAT testing. After the observation period, the experimental animals were sacrificed, and the limbs were removed. Thrombus samples were stained with hematoxylin and eosin (HE), and the wet weight of the thrombus was measured. Results: The thrombosis incidence in plateau group D was significantly higher than that in group B, accompanied by a marked increase in blood viscosity and hematocrit (P<0.01). Additionally, levels of endothelin-1, interleukin-6, and tissue factor were significantly elevated (P<0.05), indicating a coagulation disorder. Conclusion: A model of quantitative coarctation of the inferior vena cava, combined with a specialized environmental chamber to simulate a plateau hypoxic environment, can be successfully established. The findings suggest that a plateau hypoxic environment promotes venous thrombosis.