Afferent loop syndrome is a rare complication which can occur in patients with Billroth II gastrectomy. Bile and pancreatic juice is congested at afferent loop in the syndrome. This syndrome can progress rapidly to necrosis, perforation, or severe sepsis, and therefore early diagnosis and swift surgical intervention is important. But, cases of endoscopic or percutaneous transhepatic drainage have been reported when surgical management was inappropriate to proceed. We report a case of afferent loop syndrome accompanying acute cholangitis developed after percutaneous transhepatic cholangioscopic lithotripsy for the retrieval of common bile duct stone in a patient who underwent Billroth II gastrectomy due to early gastric cancer. There was no other organic cause. We treated afferent loop syndrome successfully by performing balloon dilation of afferent loop outlet.