This retrospective study evaluated 112 patients who had undergone surgery by typhoid perforation at the Belen Hospital, Trujillo, Peru, from 1967 trough 1990 in order to identify by univariate analysis the combination of factors predictive of postoperative morbidity and mortality. All the patients had one or more of the following diagnostic criteria: bacteriologic, serologic, anatomopathologic and surgical. The surgical procedures performed were: simple closure (n = 70), intestinal resection in conjunction with primary anastomosis (n = 6), intestinal resection plus ileostomy (n = 33), whilst peritoneal drainage operations were used in 3 cases. The following parameters were evaluated: age, sex, length of history, length of perforation, low intestinal hemorrhage, leukocyte count, type of peritoneal fluid and number of perforations. The operative mortality rate for all patients was 21.4% and morbidity rate was 80.4%. Significant differences in morbidity were only found in patients with perforations over 48 hours (p < 0.05). Analysis of post-operative mortality: length of perforation over 48 hours (p < 0.001), presence of hematochezia (p < 0.01), leukopenia (p < 0.05), fecaloid peritoneal fluid (p < 0.05) or the evidence of 3 or more intestinal perforations (p < 0.05). We concluded that a surgeon must take into account all of these factors to lead to satisfactory results.