Abstract 1. 1. An experimental comparative study on isolated guinea pig lungs was carried out to determine the effect of selenium added to pulmoplegic solution on ischemic lung preservation. 2. 2. Two different types of solutions (Eurocollins in control group and Eurocollins + selenium 10 −3 M in experimental group) were infused before 3 hr of normothermic ischemia. 3. 3. Tissue malone dialdehyde (MDA) and tissue glutathione (GSH) levels were assessed before the ischemic period, after the ischemia and at the end of reperfusion. Electron microscopic changes were also studied at the end of reperfusion to compare the cellular injury between the groups. 4. 4. Addition of selenium before the ischemic period relatively decreased tissue MDA levels after reperfusion but did not alter tissue GSH levels.