Hematologic malignancies, in particular T-cell lymphomas/leukemias, are prevalent in patients with ataxia telangiectasia (AT), with most reported cases being clinically aggressive and high grade. Epstein-Barr virus (EBV) is often associated with lymphoid proliferations/neoplasms arising in immunodeficient patients. Reports of low-grade B-cell neoplasms in the ataxia telangiectasia population are extremely rare. Here, we describe a case of EBV-associated extranodal marginal zone lymphoma (mucosa-associated lymphoid tissue lymphoma) of the parotid gland in a 16-year-old boy with AT. In addition, we review the literature of hematologic malignancies in the AT population as well as the occurrence of EBV in mucosa-associated lymphoid tissue lymphoma.