Organophosphate intoxication may be caused pancreatitis, but the role of diagnostic imaging for pancreatitis in these patients has not been well defined. We recently encountered a patient with organophosphate poisoning showing hyperamylasemia who was proven to have severe acute pancreatitis by CT findings. The patient was a 69-year-old woman who presented to a local hospital with disturbance of consciousness. She was initially treated for cerebral infarction, but an extremely low level of ChE was noted on Day 3. The patient was then referred to our institution. Examination of the abdomen revealed weak intestinal peristalsis, blood chemistry showed an increased level of serum amylase, and the urinary organophosphate test was positive. Based on the findings obtained by abdominal CT scanning, severe acute pancreatitis was diagnosed. Clouding of her consciousness resolved on day 21, but a pancreatic pseudocyst was detected on day 41.