Clinical studies have confirmed that indomethacin (Indo) can reduce the incidence and severity of post-endoscopicretrogradecholangio-pancreatography pancreatitis (PEP) effectively. However, the role of Indo on severe acute pancreatitis (SAP) is not clear. In the present study, we aimed to explore the effects of Indo treatment on SAP model induced by caerulein combined with lipopolysaccharide. After intraperitoneal injection of Indo in mice, both the severity of SAP and the serum levels of amylase, lipase, and proinflammatory cytokines were decreased. Furthermore, the mRNA and protein levels of NLRP3 inflammasome pathway (NLRP3,ASC and IL-1 beta) in pancreatic tissues were down-regulated. In vitro experiments, by isolating the pancreatic acinar cells (PACs) from mice, we found that Indo significantly reduced lactate dehydrogenase(LDH) excretion, increased the cell activity, and inhibited the NLRP3 inflammasome pathway of PACs. Taken together, our data showed that Indo could protect pancreatic acinar cell from injury by inhabiting NLRP3 pathway and decreased the severity of SAP accordingly. (C) 2017 Published by Elsevier Inc.