Granulocytic sarcoma is an extramedullary tumor of immature myeloid cells. Such tumors may be located in any part of the body. We report a case of isolated granulocytic sarcoma of finger; which, to our knowledge, is the first report of that localization. A thirty-year-old woman with acute myeloid leukemia (AML) presented with progressive swelling and onychoptosis at her right fourth finger. The distal phalanx was excised and the tumor turned out to consisted of atypical myeloid cells, infiltrating bone trabeculae. Despite its rarity, considering myeloid sarcoma of the finger as a possible diagnosis may prevent inappropriate treatment in leukemia patients.