Severe acute pancreatitis (SAP) is one of the most dangerous abdominal emergencies in digestive system diseases, characterized by rapid onset, serious complications and high mortality rate. SAP constantly leads to peripancreatic/pancreatic necrosis, severe systemic inflammatory response and multiple organ failure, among which gastrointestinal failure and intestinal flora disorder are the key links during the aggravation of acute pancreatitis (AP). With the increasing incidence of SAP year by year, it becomes urgent to identify more effective treatment for early-stage SAP. Intestinal cleansing is an effective treatment for SAP. The main mechanisms include reducing the levels of intestinal inflammatory cytokines, decreasing gut pathogenic microorganisms, limiting the displacement of intestinal flora, increasing the abundance of probiotics to maintain flora balance, protecting the integrity of intestinal barrier function, and further lowering the occurrence of complications such as systemic inflammatory response syndrome, thereby preventing the incidence and progression of SAP and improving clinical prognosis. In this article, research progress in intestinal cleansing for improving intestinal function and treating SAP was illustrated.