INTRODUCTIONIn urgent surgical procedures for perforated peptic ulcer (PPU), there is considerable postoperative morbidity and mortality. The overall mortality rate is about 9-27%.1-3 A large number of prognostic factors for morbidity and mortality in patients with perforated peptic ulcer have been reported. [2][3][4][5][6][7] Several clinical scoring system have been proposed for prognostic prediction. The most wellknown predicted scoring system is Boey score 3, which predicted mortality in PPU patients base on the time from perforation to admission, pre-operative systolic blood pressure and comorbid conditions of patients. Then Boey score was classified in three groups, score 0, 1 and 2 and mortality rate were 0%, 10% and 100% respectively. Lohsiriwat et al was found that a higher Boey score was associated with increasing rates of both morbidity and mortality and could be considered as a simple and appropriate prognostic marker in the management of PPU. 1The American society of anesthesiologists (ASA) classification is the most commonly used for assessing perioperative risk worldwide. It is graded in six categories; depend on the patient's pre-operative health status. 5 The previous study found that ASA classification ABSTRACT Background: To determine the accuracy of Boey score, American society of anesthesiologists (ASA) score, peptic ulcer perforation (PULP) score and the mannheim peritonitis index (MPI) score and compare each predicted scoring systems for prediction the morbidity and mortality of patients with perforated peptic ulcer. Methods:We retrospectively reviewed the patients with gastric or duodenal ulcer perforation in Bhumibol Adulyadej Hospital, Bangkok, Thailand between 1 January 2008 and 31 December 2012. The morbidity and mortality within 30 days of the PPU patient who underwent the surgical procedure was determined. The predicted scoring systems included Boey score, ASA score, PULP score and MPI score were calculated. We used area under curve of receiver operating characteristics curve to compare the scoring accuracy. Results:The study included 140 patients, Female 17.9% and male 82.1%. The mean age was 48.5 years. The most common site of PPU was the pre-pyloric region (80%). The most common operative procedure was the simple suture with omental graft. The complication rate was 20.71%. Overall mortality rate was 3.57%. The AUC for morbidity prediction was 0.671 for Boey score, 0.684 for ASA score, 0.698 for MPI score and 0.727 for PULP score. The AUC for mortality prediction was 0.728 for Boey score, 0.776 for ASA score, 0.771 for MPI score and 0.784 for PULP score. Conclusions:The PULP score may be the better prognostic scoring system for post-operative morbidity and mortality of PPU patient than Boey score, ASA and MPI.