Bacterial translocation (Bt) from the gastrointestinal (GI) tract to systemic organs creates the possibility of Infection and sepsis in a great number of pathologic entities. In a mouse model of Intestinal Obstruction (IO), we evaluated the type of micro-organisms and the organs that bacteria frequent translocated. At 24 hours post-10, positive cultures where obtained at the MLN, portal, systemic circulation and peritoneal cavity, establishing that the translocation is bi-directional. The more frequent bacteria isolated were the Streptococcus group D, Proteus mirabilis, Escherichia coli, Pseudomonas sp., an clostridium. BT occurs at 24 hour post-OI and was due to increased intestinal permeability, at 48 hrs BT increased and related to the physical disruption of the mucosal barrier in the intestinal mucosa. Cell mediated immunity (CMI) response in this model was not altered, although a progressive decrease was observed at 48 hrs it was not significant, suggesting that the CMI play no role in the pathogenesis of BT. In the Control-Laparotomy group, CMI response was increased significantly at 48 hours, suggesting that a simple laparotomy boost the immune defense response.