The clinicopathologic review of 33 well-documented cases of granulocytic sarcoma on file in the Registry of Ophthalmic Pathology confirmed the facts that this tumor is encountered mainly in children, that boys are affected more frequently than girls, and that white Americans appear to be less vulnerable than other ethnic groups. While granulocytic sarcoma is a variant of granulocytic leukemia, the tumor may appear before, after, or concomitantly with hematologic evidence of leukemia. In the present series only four of the 33 patients were already known to have leukemia when they were first seen by an ophthalmologist for their orbital, ocular, or adnexal lessions. The Leder stain has proved extremely helpful in arriving at a definitive histopathologic diagnosis. Accurate diagnosis is important to prevent inappropriate medical or surgical treatment and to indicate the need for vigorous antileukemic chemotherapy. Prognosis at best is poor.