Abstract： Objective To study the risk factors of spontaneous bacterial peritonitis(SBP) in cirrhotic patients with ascites. Methods The clinical data of 186 cirrhotic patients with ascities from February 2005 to March 2010 were retrospectively analyzed were divided into two groups,the one with SBP and the other without SBP. The following factors such as sex, Child-Pugh grade were analyzed with binary logistic regression. Results Among those factors ,3 factors were proved to be risk factors for SBP in cirrhotic patients with ascites by analysis of single and multiple variables. Those were Child-Pugh grade score, serum bilirubin level and ascitic fluid albumin. Conclusion SBP in cirrhotic patients with ascites was affected by many factors. The Child-Pugh grade score, serum bilirubin level and ascitic fluid albumin were independently associated with risk factors of SBP, so it was important to pay attention to those factors in preventing the onset of SBP.