摘要:Non-Hodgkin’s lymphoma is a heterogeneous malignancy originating from proliferation of lymphoid cells or their precursors. , we report a case of a 6-year-old Iranian male child admitted at the Department of Oral Medicine, School of Dentistry, Mashhad, Iran, in March 2019. The case was complaining about gingival swellings worsening for one month. Clinical and pathologic examination, complemented by biopsy and immunohistochemistry, confirmed the diagnosis of high-grade B-cell non-Hodgkin’s lymphoma. Treatment was based on chemotherapy. Intraoral involvement of lymphomas might be confused with inflammatory diseases; therefore the dentist has a crucial role in early diagnosis for appropriate management of the disease.