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Background One of the most crucial issues in liver transplantation is the gap between the increasing number of patients waiting for a transplant and the shortage of available grafts. This limitation has led many liver transplant units to include for surgery organs defined as “marginal” or “sub-optimal” due to hepatic steatosis or sourcing from non-heart-beating donors (NHBD). In turn, the marginality of these organ donors is proportional to a high incidence of liver dysfunction after transplantation due mainly to more severe ischemia-reperfusion injury events. The use of new methods of preservation of hepatic grafts like Machine Perfusion becomes necessary, especially for its ability to reduce the damage of ischaemia-reperfusion in hypothermia. This opens an interest towards the use of alternative methods in preserving hepatic graft as Machine Perfusion, able to reduce this type of insults and allow the dosage of biomarkers that can predict the extent of damage ischemia-reperfusion injury and the quality of functional recovery of the graft after transplantation. The great potential of this system in the context of organ preservation and the numerous studies in the literature led us to investigate this issue. Purpose The aim of our work was to carry out an experimental model of Machine Perfusion (MP) for the preservation of livers procured from non heart-beating donor, as a viable alternative to the traditional Cold storage (CS) at 4°C. A further aim of our project was to identify biomarkers that can be used as predictors of postoperative graft damage. Material and methods We used 10 Landrace pigs of about 20 kg to which we performed, 60 minutes after cardiac arrest, total hepatectomy, thus harvesting the liver. The animals were divided into two groups: in the first group (Group A) 5 livers was preserved for 6 hours in MP at 20° C. In the second group (Group B) 5 livers was stored for 6 hours in CS. In all study groups the period of preservation was followed by reperfusion in normothermic MP (37 °) with whole oxygenated blood previously collected from the donor animal for 2 hours to assess the response to reperfusion. During the experiment blood samples and histological specimens were collected. Results Graft preservation by Machin perfusion at 20°C is superior compared to the Cold Storage, both from biochemical (AST, ALT, LDH, lactate) and histological standpoint (necrosis and congestion). The dose of AST, ALT, LDH and lactate has proven be a reliable parameter for the assessment of organ damage and functional recovery of the graft liver. The dosage of cytokines such as IL1, IL6, TNF alpha showed no significance. Conclusion These experimental evidences highlight the effectiveness of a preservation with continuous perfusion at 20° C on a large animal model. Both from biochemical that histological standpoint, we have observed that Machine Perfusion in moderate hypothermia is beneficial in the preservation of the graft and offers the considerable advantage of being able to test, during perfusion, biomarkers that can predict hepatic graft recovery, before transplant, in order to reduce the incidence of post-transplant graft disfunction.