Abstract: Objective: To investigate the risk factors of intra abdominal hypertension( IAH) in severe acute panreatitis( SAP) patients and assess the prognosis of SAP patients with IAH. Methods: Fifty-eight SAP patients was monitored intra-abdominal pressure indirectly via urinary bladder pressure,repeated or continuous intra-abdominal pressure 12 mmHg was set as IAH. Multivariate logistic regression analysis was applied to analyze the effects of parameters including age,gender,acute physiology and chronic health evaluation Ⅱ( APACHEⅡ) scores,24 h fluid balance,hematocrit,serum calcium level on IAH. The influence of IAH on rates of operation, infection,multiple organ dysfunction syndrome,use of vasoactive agent,mechanical ventilation,acute kidney injury,positive blood culture,hospital duration,length of intensive care unit stay and mortality were also investigated. Results: The logistic regression analysis displayed,the first 24 h fluid balance,APACHE Ⅱ scores and serum albumin level were the independent risk factors for IAH in patients( P 0. 05). Moreover,patients with IAH had significantly longer average length of hospital and intensive care unit duration,higher rates of systemic and local complications and more invasive treatments compared with those without IAH( P 0. 05 to P 0. 01). Conclusions: The first 24 h fluid balance,APACHE Ⅱ score and serum albumin level were found to be independent risk factors for IAH in patients. It played the important role to relieve the possible risk factors of IAH promptly when treatment of SAP.