Peritonitis (Peritoneal inflammation) may be primary, secondary or tertiary. Typhoid ileal perforation lead to secondary peritonitis that is a life threatening condition. Assessing the severity of peritonitis is important step in determining the proper treatment plan. AIM: This study is aimed to assess the ability of modified APACHE II (Acute Physiology and Chronic Health Evaluation II) score to correctly assess the severity of generalized peritonitis secondary to ileal perforation. MATERIALS AND METHODS: 100 patients of peritonitis secondary to ileal perforation were chosen in a one year period and were applied modified APACHE II score to assess the severity and outcome. RESULTS: Most of perforation occurred in 2nd and 3rd decade (65%). APACHE II score ranged from 1 to 21. Most of patients had < 9 score. Higher APACHE II score was associated with increased mortality. Morbidity was also accurately predicted by APACHE II score. CONCLUSION: Typhoid ileal perforation is still a common health problem causing high mortality (11%). Compared to mortality, morbidity was less accurately predicted by APACHE II score, and more number of the patients developed more complication in higher APACHE II score group. HOW TO CITE THIS ARTICLE: