We are presenting a case of Listeria monocytogenes spontaneous bacterial peritonitis (SBP) monomicrobial non-neutrocytic bacterascites (MNS) in a patient with malignant ascites secondary to cholangiocarcinoma who underwent peritoneal catheter placement. Listeria peritonitis is uncommon, with cancer patients at a higher risk. Listeria infection should be suspected in susceptible patients once there is no response to empiric antibacterial or if the initial culture report shows gram positive bacilli, the antibacterial of choice is ampicillin.