Granulocytic sarcoma (chloroma) is an uncommon malignant neoplasm associated with myelogenous leukemias. Its appearance may precede the clinical manifestations of the acute leukemic phase by months to years. We report the CT findings of a case bilateral intraorbital granulocytic sarcoma which preceded the blast phase of acute myelogenous leukemia (AML) and led to its diagnosis. An awareness of granulocytic sarcoma and its CT appearance may expedite the diagnosis of AML or prompt close monitoring of those cases of granulocytic sarcoma antedating the appearance of AML.