Objective To assess the possible causes of acute pancreatitis (AP) in long term peritoneal dialysis (PD) and hemodialysis (HD) patients, and to discuss the diagnosis and treatment of AP in this kind of patients. Methods The clinical data of 9 cases of AP in PD and HD patients who were admitted in the hospital during January 1993 and January 2000 were analysed retrospectively. Results The serum levels of amylase of all the 9 cases were over three and a half times of upper limit value of healthy subjects. B mode ultrasound and CT scan examinations were useful for diagnosis of AP. Eight patients recovered very well with conservative treatment, while one patient who was diagnosed as acute severe pancreatitis and complicated with shock died. Conclusion Long term PD and HD patients are predisposing to develop AP. Diagnosis of AP in these patients primarily depends on the detection of serum amylase. Dialysis treatment is indispensable for cure of AP.