We report a patient with acute myeloid leukemia (AML) presenting with generalized lymphadenopathy, clinically simulating aggressive non-Hodgkin’s lymphoma. This patient presented with anemia and bulky lymphadenopathy in the oropharyngeal (Waldeyer’s ring), submandibular, supraclavicular and inguinal nodal regions. Lymph node biopsy was initially suggestive of a T-cell lymphoblastic lymphoma, based on morphologic features together with positive immunohistochemical staining for CD7 and CD43 (Leu 22). Definitive diagnosis of AML was established when a more detailed immunophenotypic analysis showed expression of the myeloid markers CD13 and CD33, and by the demonstration of rare Auer rods and positive peroxidase staining in bone marrow blast cells. Although this is a rare presentation, AML must always be considered in the clinical and pathologic differential diagnosis of aggressive non-Hodgkin’s lymphoma.