We have previously reported that perfusion using warm oxygenated buffer before cold preservation (preperfusion) improved the viability of liver grafts from non-heart-beating donors. We demonstrated that adenosine triphosphate content was restored and apoptosis was reduced. The objective of the present study was to evaluate mitochondrial functions after this preperfusion and the effects of addition of prostaglandin E 1 (PGE 1) to the preperfusion buffer. Preperfusion improved portal flow, bile production, and mitochondrial function, and reduced alanine aminotransferase levels in the perfusate. Addition of PGE 1 significantly increased bile production and suppressed alanine aminotransferase and tumor necrosis factor-α levels. PGE 1 minimized mitochondrial membrane damage and ischemic injury after liver graft reperfusion. Release of mitochondrial cytochrome c was suppressed by addition of PGE 1. In conclusion, perfusion using oxygenated buffer containing PGE 1 before cold preservation significantly prevented cellular damage, protected mitochondrial function, and suppressed the release of mitochondrial cytochrome c in livers undergoing warm ischemia-reperfusion injury. This method shows promise for reducing cellular damage in non-heart-beating donor liver grafts.