Ascariasis is the most common helminthic infection of human beings. The causative organism is ascaris lumbricoides. This organism usually lives in the small intestine. Rarely, however, it may enter into the biliary tree via the ampulla of vater.A 35-year-female presented to the surgical outpatients department complaining of a colicky pain in the right upper abdomen and nausea over the past three days. On examination, she was found to be icteric and she displayed tenderness in the upper abdomen. Her laboratory investigations revealed low haemoglobin (9 gm%) and raised direct bilirubin (2.4 mg%) and alkaline phosphatase (304 IU). Abdominal sonography depicted a distended gallbladder and sludge in the common bile duct. Magnetic Resonance Cholangio-Pancreatography (MRCP) showed a tubular structure in the common bile duct (Figure 1). A diagnosis of biliary ascariasis was made, and the patient was started on albendazole 400 mg once a week for three weeks. The patient improved symptomatically with this conservative treatment.Biliary ascariasis is more common after sphincterotomy or biliary-enteric anastomosis. Pregnant females are also more prone probably because of the relaxing effect of hormones on the biliary smooth muscles. It often presents as abdominal colic, cholecystitis, cholangitis, pancreatitis etc. Gallbladder ascariasis is less commonly seen due to a narrow and tortuous cystic duct. About 95% of patients respond well to medical management. Medical management fails if there is a distal stone or stricture in the common bile duct. Surgical intervention in the form of endoscopic removal, laparoscopy or open surgery may be required in such cases [1-3]. Figure 1.