Abstract: Objective: To investigate the clinical value of the percutaneous catheter drainage(PCD) guided by ultrasound in severe acute pancreatitis(SAP) complicated with peripancreatic effusion.Methods: Seventy-three patients with SAP were randomly divided into the observation group(38 cases) and control group(35 cases).The control group and observation group were treated with conservative therapy and PCD guided by ultrasound ocmbined with conservative therapy,respectively.The recovery time of abdominal pain,abdominal distention,serum amylase and urine amylase,time of antibiotic use,hospital stay,cure rate,mortality and incidence rate of local complication,and leukocyte count,procalcitonin,serum calcium and pressure change of abdominal cavity in certain time between two groups were compared.Results: Compared with the control group,the recovery time of abdominal pain,abdominal distention,serum amylase and urine amylase,time of antibiotic use and hospital stay in observation group were significantly shorter(P<0.01),and the leukocyte count,procalcitonin,serum calcium and pressure change of abdominal cavity in certain time decreased in observation group(P<0.05 to P<0.01).The differences of the treatment effect and incidence rate of complication bettween two groups were not statistically significant(P>0.05).Conclusions: The treatment of the SAP complicated with peripancreatic effusion with PCD guided by ultrasound is good effect,low complication,safe and reliable,which has great application value in clinic.