[Objective] To establish the animal model of moderate lung injury caused by hyperoxia in rats,and measure the alveolar fluid clearance.[Methods] Rats were exposed to 90% oxygen.AFC,TLW,and EVLW were calculated in rats exposed to hyperoxia for 24 h and 48 h.The effect of amiloride? ouabain and terbutalin on AFC was tested in hyperoxic exposure and room air-exposed rats.[Results] There was significant difference in TLW and EVLW in rats with hyperoxic exposure compared to room air exposure.However,AFC did not change.Amiloride and ouabain can reduce the AFC in both room air-exposed and hyperoxic-exposed rats.There was no significant difference in the magnitude of the terbutalin-stimilated AFC in rats with hyperoxic exposure compared with room air-exposed rats.[Conclusion] In the setting of moderate lung injury,the alveolar epithelial barrier is still capable of removing fluid at a normal arte.