Objective To explore the protective effect of aprotinin contained LPD ( low potassium dextran) solution via an in situ rabbit lung preservation model. Methods Thirty New Zealand rabbits were divided randomly into 3 groups, 10 in each group. In group A (control group), the left lung hilus was clamped without solution perfusion; In group B ( LPD group) and group C ( aprotinin group), the lungs were perfused with LPD solution and aprotinin contained LPD, respectively. The lungs in all groups were stored at 10 centigrade in a specially made lung preservation container for 2 hours and then unclamped the lung hilus to rcperfuse the lung for 2 hours. Pulmonary venous blood samples were collected at pre-clamping of lung hilus,5 minutes and 120 minutes after reperfusion for analysis of blood gas. Biopsy of lung tissue was excised for morphological examination at pre-unclamping of lung hilas and 2 hours after reperfusion. Examination of bronchoalveolar lavage fluid was taken for the evaluation of inflammation status. Results Pulmonary venous partial pressure of oxygen ( PvPO2) in the 3 groups at 5 minutes and 120 minutes after reperfusion were significantly higher than those before clamping of lung hilus,respectively. PvPO2 in group A and group B at 120 minutes after reperfusion were significantly higher than those at 5 minutes after reperfusion. There was no significant difference of PvPO2 in group C between 5 minutes and 120 minutes after reperfusion. PvPO2 in group C at 5 minutes and 120 minutes after reperfusion were significantly higher than those in group A and group B. The morphological lesion was more severe in group A and B than that in group C. The PMN percentage in bronchoalveelar lavage fluid in group A and B was significantly higher than that in group C. Conclusions The protective effect of aprotinin is obvious for lung protection in animal model. Aprotinin contained lung preservation solution is superior to LPD for lung protection.