Spontaneous bacterial peritonitis (SBP) is the most common infection in liver cirrhosis patients, and is not a result of surgery or intra abdominal infection. Argon plasma coagulation (APC) is an endoscopic procedure used with a high-frequency electrical current for control of bleeding from gastrointestinal vascular ectasias including angiodysplasia and gastric antral vascular ectasia. This procedure is known to be safe because it uses a noncontact method. Therefore, tissue injury is minimal and up to two to three millimeters. However, we experienced a case of SBP occurring immediately after performance of APC for control of severe bleeding from angiodysplasia in the colon in a patient with liver cirrhosis and hepatocellular carcinoma.