Listeria monocytogenes is an uncommon cause of illness in the general population. Meningoencephalitis is the most common central nervous system (CNS) manifestation of listeriosis. However, brain abscess represents 1-10% of all CNS listeriosis. To our knowledge, L. monocytogenes brain abscess in multiple myeloma patients has not been previously reported. Thus we report a 58-year-old male patient with multiple myeloma who developed a brain abscess due to L. monocytogenes. Due to a history of penicillin allergy, he was treated with intravenous trimethoprim/sulfamoxazole (TMP-SMX) for a total of 12 weeks, and gentamicin for the first two weeks, followed by oral therapy of TMP-SMX for a total of nine months. He is alive six and a half years after the diagnosis of myeloma with occasional brief seizures despite being on two anticonvulsants.