Lymphomas are a group of malignant diseases affecting the lymphoreticular system. Lymphoma is the second most common neoplasm of the head and neck after squamous cell carcinoma, but the incidence of lymphomas in the oral cavity and orbit is rare. Non-Hodgkin's lymphoma (NHL) is less predictable than Hodgkin's but has a greater predilection to extranodal tissues. Non-Hodgkin's incidence in extranodal sites accounts for about 20% to 30%, but in the oral cavity, its around 0.1% to 5%. The rarity of incidence in the oral cavity and atypical radiographic features diagnosing a lymphoma is quite a challenge for clinicians. Here we describe a case of 31-year-old male patient with high-grade non-Hodgkin's lymphoma involving oral cavity with metastasis to orbit, skeletal structures, testes, liver, pancreas and nasopharynx, which is quite rare.