【Objective】 To investigate the therapeutic effect of Huaier on acute pancreatitis (AP) and its potential mechanism. 【Methods】 A mouse model of cerulean-induced AP was used to verify the therapeutic effect of Huaier in vivo. HE staining and immunohistochemical staining were used to evaluate the histopathological changes of the pancreas, and transmission electron microscopy was used to observe the pyroptosis morphology of the pancreas. In vitro, 266-6 cell line was used as the experimental carrier to verify the protective effect of Huaier on acinar cells. Electron microscopy and Western blotting were used to evaluate the pyroptosis level of acinar cells, and ROS fluorescence probe was used to detect the oxidative stress state of acinar cells. 【Results】 Huaier significantly alleviated the severity of AP in mice. HE staining of pancreas showed that necrosis and inflammatory cell infiltration were reduced, and the level of serum amylase was decreased. Immunohistochemical staining and Western blotting showed that Huaier effectively inhibited the expressions of pyroptosis-related molecules such as NLRP3 and GSDMD in pancreatic tissue. Electron microscopy showed that Huaier could reduce the pyroptosis level of pancreatic acinar cells under inflammatory state. In addition, the level of ROS in acinar cells was significantly reduced after the intervention of Huaier, and ROS-mediated pyroptosis of acinar cells could be effectively inhibited by Huaier. 【Conclusion】 Huaier can effectively reduce the severity of AP by inhibiting ROS-mediated pyroptosis of acinar cells.