Background/Aims: Despite the presence of several diagnosis scales for delirium, no prediction scale that is specific for postoperative delirium after abdominal surgery is available. We sought to create a novel delirium prediction system that is specific for abdominal surgery. Methods: This study included 213 consecutive patients who required management in the surgical ICU following abdominal surgery. The Neelon and Champagne (NEECHAM) Confusion score was monitored throughout the postoperative course and patients with low NEECHAM score (≤26) were diagnosed as having delirium. Results: Seventy-three patients (34%) were categorized in the delirium group. Multivariate analyses indicated that an age >70 years, hypertension, those undergoing hepatopancreatobiliary or upper gastrointestinal surgeries, a serum albumin level <2.5 g/dl on postoperative day (POD) 3 or 5 and a ≥6 mEq/l gap in the serum sodium level between the preoperative value and that on POD 3 were independently associated with a low NEECHAM score (≤26). When the presence of each risk was counted as 1 point, 21 patients had ≥4 points and 15 of them (71%) had low NEECHAM score. Conclusion: The scoring system combining multiple risk factors may be useful for predicting patients with an elevated risk for postoperative delirium after abdominal surgery.