We describe a 40-year-old woman with a history of precursor T-cell acute lymphoblastic leukemia who developed an orbital mass associated with diffuse infiltration of the paranasal sinuses. The clinical and radiologic findings suggested an orbital abscess. Examination of orbital and ethmoid sinus biopsy specimens revealed relapse of precursor T-cell acute lymphoblastic leukemia. Although orbital involvement by granulocytic sarcoma (also known as extramedullary myeloid cell tumor and chloroma) with or without concurrent acute myeloid leukemia is well described in the literature, similar presence of acute lymphoblastic leukemia of either precursor T-cell or B-cell lineage is rare.