Granulocytic sarcoma (GS) is a rare extramedullary malignant tumor composed of immature myeloid cells. It is strongly associated with acute myeloid leukaemia, chronic myeloproliferative diseases. Occurrence of GS in the oral cavity is extremely uncommon. Present case reported an unusual occurrence of GS without leukemia involving maxillary sinus of a child. The patient underwent chemotherapy followed by radiotherapy with complete remission. A long-term follow-up of the patient was carried without any evidence of recurrence with special focus on diagnostic difficulties. The present case highlights the perplexity in diagnosing such lesions with emphasis on the need of careful interpretation of all clinical, radiographic, histopathological and immunohistochemical details as it is one of the most frequently misdiagnosed disorder.