Brachial plexus neuropathy is a rare, but underdiagnosed condition, characterized by intense analgesic-resistant shoulder pain, followed by brachial plexus paresis and sensory symptoms. We present a case of brachial plexus neuropathy, induced by Toxoplasma gondii (T. gondii) 17 days after allogeneic hematopoietic stem cell transplantation (alloHSCT) in a patient with acute myeloid leukemia. The diagnosis was made based on the clinical presentation, magnetic resonance imaging (MRI) of the brachial plexus, and positive T. gondii polymerase chain reaction (PCR) in cerebrospinal fluid. The patient was treated with pyrimethamine, sulfadiazine, and levofolinic acid during 6 weeks, with a positive outcome. K E Y W O R D S allogeneic hematopoietic stem cell transplantation, brachial plexus neuropathy, Toxoplasma gondii How to cite this article: De Clercq J, Crevits I, Reynders M, Deeren D. Toxoplasma gondii-induced brachial plexus neuropathy after allogeneic hematopoietic stem cell transplantation. Transpl Infect Dis. 2019;21:e13157.