The chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an unusual but important complication of hematopoietic stem cell transplantation (HSCT) rarely reported to date. We describe a 17-year-old woman with a diagnosis of acute myeloid leukemia due to Fanconi's anemia who was submitted to allogeneic HSCT and developed CIDP as part of graft-versus-host disease. Investigation showed high cerebrospinal fluid protein; electrophysiological studies revealed sensory-motor demyelinating polyradiculoneuropathy; muscle and nerve biopsy were compatible with CIDP.