We aimed to characterize the blood reflux, blood compatibility, and biocompatibility of a blood pump after deactivating the pump in an animal in order to facilitate further studies and clinical application. Methods A left- ventricular assist device was implanted into a healthy sheep via a left thoracic approach. After 6 weeks of normal operation, the pump was stopped, as was warfarin administration. The physiological status of the animal was then monitored, and blood biochemical and coagulation testing was performed before the procedure and between 1 and 12 weeks after the pump was deactivated. Ultrasonographic examination was performed 16 weeks after the pump was deactivated. Results The left-sided cardiac assistance model was established successfully, and 6 weeks after deactivation of the pump the sheep displayed normal behavior and normal physiology, with no significant changes in the test result . Ultrasonography showed that the artificial blood vessel was not blocked and there was reverse blood flow 16 weeks after the blood pump was stopped. Conclusions Deactivation of a blood pump was not associated with effects on blood compatibility, physiological state, or organ function in a sheep. The artificial blood vessel was not obstructed, no thrombosis was found, and left-sided cardiac function was not significantly affected. Thus, this blood pump has good compatibility, and the study has provided a reference for the clinical treatment of unexpected pump failure. Further studies should assess the impact of low-dose anticoagulant therapy and repeated deactivation on physiology and cardiac function.