A 79-year-old man presented to our hospital with complaints of itchiness and jaundice. Contrast-enhanced computed tomography scan revealed an approximately 20-mm poorly enhanced area in the head of the pancreas and a dilated common bile duct. The patient was diagnosed with obstructive jaundice associated with pancreatic head cancer. Preoperative biliary drainage was performed using a plastic stent. Subsequently, he developed biliary infection; we performed stent exchange and initiated antibiotic therapy. However, these approaches did not completely resolve the biliary infection, and we performed percutaneous transhepatic gallbladder drainage and bile culture. Eventually, pancreaticoduodenectomy was performed on day 30 of hospitalization. Bile culture test results showed that Enterococcus faecium caused biliary infection on the postoperative day 1. We switched the antibiotics to vancomycin, which is effective against E. faecium. His postoperative course was favorable, and he was discharged on postoperative day 45.