Non-Hodgkin's lymphoma (NHL) patients who have bone involvement are rarely seen. These patients exhibit very different clinical manifestations in comparison with the normal cases of these types of cancers. We report a case of NHL, firstly treated as osteomyelitis case of unidentified etiology. This case showed the difficulties that may occur while diagnosing this issue. The histopathological diagnosis is the final confirmation of this disease. Moreover, the primary and essential treatment for these patients is chemotherapy.