Objective To summarize the related risk factors and preventive measures of acute pancreatitis (AP) combined with portal vein system thrombosis (PVST). Method The literatures on the general clinical characteristics, pathogenesis, risk factors and prevention prognosis of AP with PVST in recent years at home and abroad were reviewed. Results The incidence of AP combined with PVST was increasing, and the pathogenesis was complex, primarily related to pancreatitis and direct venous compression, which caused blood flow stagnation and hemodynamic disturbance, followed by induced venous thrombosis. Pancreatic necrosis, peripancreatic fluid volume accumulation and the severity of pancreatitis were the main risk factors for the onset of pancreatitis. Other local and systemic factors such as coagulation dysfunction, malnutrition, esophageal and gastric varices had also been reported in the literatures. At present, the prevention methods reported in relevant studies include anticoagulation treatment, pancreatic surgery debridement and drainage, nutritional support, systemic and local inflammation intervention, and early fluid resuscitation, etc. Conclusions The risk factors and pathogenesis of AP combined with PVST are complex and diverse, which requires early identification by clinical workers, early intervention and treatment to avoid or reduce the occurrence of PVST as much as possible to improve the prognosis of patients. However, some preventive measures still need further research to verify their safety and effectiveness.