Background: Argon plasma coagulation (APC) is very useful as a consolidation treatment for reducing the recurrence of esophageal varices (EVs). However, repeated sedation in endoscopic treatment has the risk of prolonging hepatic encephalopathy and affects the respiratory state of liver cirrhosis (LC) patients, in whom pulmonary arteriovenous shunts are observed. We evaluated prospectively whether transnasal endoscopic APC without sedation is more effective than peroral endoscopic APC with sedation. Patients and Methods: LC patients (n = 101), treated by endoscopic injection sclerotherapy to eradicate EVs, were randomly divided into a transnasal APC group (n = 50) and a peroral APC group (n = 51). The primary efficacy endpoint was the cumulative recurrence rate of EVs. The secondary endpoints were blood pressure (BP), heart rate, oxygen saturation during APC and complications. Results: There was no significant difference in the cumulative recurrence rate of EVs at 36 months between the transnasal APC and peroral APC groups (35.0 vs. 40.8%, p = 0.39, log-rank test), indicating that transnasal APC is not inferior to peroral APC. The transnasal APC group showed more stable intraoperative BP and oxygen saturation values, and a lower incidence of epigastralgia (56.0 vs. 74.5%, p = 0.04). Conclusion: The efficacy of reducing the recurrence of EVs in the transnasal APC group was not significantly different from that in the peroral APC group. Transnasal APC caused less distress and required no sedation. Therefore, this method was more advantageous for LC patients at risk of suffering from prolongation of hepatic encephalopathy.