BACKGROUND Biliary ascariasis is rare but remains the most common parasitic infection in remote areas and in people with poor medical conditions. Here, we reported a case of biliary ascariasis in order to raise awareness of possible parasitic infections. CASE SUMMARY A 68-year-old female was admitted to the emergency room of the Affiliated Hospital of Guizhou Medical University on 28 September 2017, with chief complaint of pain in the right upper abdomen. Ultrasonography of the abdomen showed that the upper segment of the common bile duct was slightly dilated with parallel tubular structures, indicative of biliary ascariasis. Endoscopic retrograde cholangiopancreatography was performed under general anesthesia on 29 September 2017, and an adult Ascaris lumbricoides worm was observed. After the worm was removed from the bile duct, the patient’s pain immediately subsided. The patient was successfully cured, without any complications. CONCLUSION This report emphasizes the need for physicians to consider biliary ascariasis as a possible cause when treating cases of biliary colic.