Objective：To explore the effect of 3D clinostat simulation microgravity effect on mice bones and heart. Methods：Twenty-five 8-week-old male C57BL/6J mice were randomly divided into 5 groups （n= 3~5）：ground control group （GC group），3-week-treated control group （TC3 group），3 weeks simulated microgravity group （SM3 group），6-week-treated control group （TC6 group），6 weeks simulated microgravity group （SM6 group）. Micro-CT was used to detect the changes of left femur parameters in mice. Results：The results showed that compared with GC group，the bone volume/tissue volume and trabecular thickness of mice in TC3，SM3，TC6 and SM6 groups were significantly decreased （P<0.05），the trabecular spaceing was significantly increased （P<0.05）. There was no significant difference in trabecular number and cortical bone wall thickness. After 3 weeks of treatment with the 3D clinostat，other heart parameters did not change compared to the thinning of the LVPW in mice. Diastolic and systolic left ventricle diameter decreased，LV Mass became lighter，and tight space led to increased stroke volume and ejection fraction. Conclusion：Microgravity effects simulated by 3D clinostat can lead to bone loss in mice，and affect the structure and function of the heart with time effect.