Objective: A syngeneic, acute, double lung transplant model in the rat was used to determine the impact of exogenous surfactant treatment on graft function after prolonged cold storage, Methods: The donor grafts were flush perfused, preserved for 16 hours, and then reperfused for 120 minutes, Untreated lungs served as controls (group I), In group II the recipient received a 200 mg/kg dose of surfactant (CuroSurf) before reperfusion. In groups III and IV, surfactant was administered before perfusion and harvesting (III, 20 mg/kg; TV, 200 mg/kg), Serial measurements of graft pulmonary vascular resistance, alveolar-arterial oxygen difference, and compliance were obtained, Final graft assessment included weight gain and histologic study, Results: Repeated-measures analysis of variance showed significant improvement of graft performance in respect to compliance, alveolar-arterial oxygen difference, and pulmonary vascular resistance in donor surfactant treatment group IV (200 mg/kg) in comparison with recipient treatment (group II) and untreated controls (group I), Reducing the donor surfactant supplementation from 200 mg/kg to 20 mg/kg (group III) improved oxygenation and lung compliance as compared with untreated controls, Grafts in groups I and II had significantly more weight gain after 2 hours of reperfusion, Recipient treatment resulted in significantly more pulmonary hemorrhage in histologic sections. Conclusion: Donor treatment with exogenous surfactant is advantageous for preservation of graft function after extended ischemia, Positive effects may be seen with as little as 20 mg/kg of exogenous surfactant given before donor organ perfusion.