Granulocytic sarcoma is a rare extramedullary tumor composed of myeloid progenitor cells. Primary involvement of the biliary tract without evidence of leukemia is exceedingly rare. Here, we report an isolated biliary granulocytic sarcoma in a 30-yr-old man who presented with jaundice, fever, and chill without any evidence of leukemia. However, five months after the diagnosis, he developed acute myelogenous leukemia with multilineage dysplasia and chromosomal abnormality. A rare possibility of biliary granulocytic sarcoma should be considered as a differential diagnosis in patients with obstructive jaundice. A histologic evaluation by aggressive diagnostic intervention is important and may improve prognosis.