Ischemia/reperfusion injury (IRI) occurs in liver transplantations and major resections and can lead to liver dysfunction. HMGB1 locates in nucleus of normal hepatocytes, but translocates to cytoplasm and the extracellular space during IRI. Although the functions of nuclear and extracellular HMGB1 are well explored, the role cytoplasmic HMGB1 plays in hepatic IRI is still unknown. We hypothesize cytoplasmic HMGB1 interacts with binding proteins involved in the hepatocellular response to IRI. In this study binding proteins of cytoplasmic HMGB1 during hepatic IRI were identified. Normal and warm ischemia reperfusion (WI/R) liver tissues were used for cytoplasmic protein extraction. The protein extracts were subjected to co-immunoprecipitation to enrich HMGB1-protein complexes. To identify the immunoprecipitated proteins in eluates, 2DE and subsequent MS detection were performed. Three identified proteins were verified using western blotting: betaine--homocysteine S-methyltransferase 1 (BHMT), cystathionine gamma-lyase (CTH) and ATP synthase beta subunit (ATP5B). All three identified proteins have a role in metabolic pathways and autophagy. Our results demonstrate cytoplasmic HMGB1 binds to BHMT, CTH and ATP5B during hepatic WI/R. Since both, cytoplasmic HMGB1 and binding proteins, are involved in autophagy, we speculate this protein complex may be involved in the hepatocellular response to IRI via the autophagy pathway.