Objectives: To identify the predictive factors of successful non-operative management of patients with intraperitoneal bleeding following blunt abdominal trauma.Methods: This was cross-sectional study being performed in our Level I trauma center in southern Iran between 2010 and 2011. We included adult (>14 years) patients with blunt abdominal trauma and intraperitoneal hemorrhage detected by CT-Scan who were hemodynamically stable and did not require any surgical intervention. Patients were managed conservatively in ICU. Those who required laparotomy during the study period were named as non-operative management failure (NOM-F) while the other were nonoperative management success (NOM-S). The baseline, clinical and laboratory characteristics were compared between two study groups in order to detect the predictors of successful NOM of intra-peritoneal bleeding.Results: Overall we included 80 eligible patients among whom there were 55 (68.7%) men and 25 (31.3%) women with mean age of 30.63.6± years. Finally, 43 (53.8%) were successfully managed conservatively (NOM-S) while 37 (46.2%) required laparotomy (NOM-F). We found that those who underwent emergency laparotomy had significantly higher ĘHb (p=0.016) and lower base deficit (p=0.005) when compared to those who were successfully managed conservatively. Those who required surgical intervention had significantly lower baseline systolic blood pressure (p<0.001) and higher shock index (p=0.002). The other parameters such as pulse rate and respiratory rate were comparable between two study groups.Conclusion: In patients with intra-peritoneal bleeding following blunt abdominal trauma, the most reliable predictive clinical and para-clinical factor of successful non-operative management are shock index and systolic blood pressure on arrival, base deficit and hemoglobin drop within first 12 hours of admission.