Bone marrow necrosis (BMN) is an entity resulting from an infarction of the bone marrow stroma without involvement of the cortical bone. It is a serious complication which is associated with malignant neoplasia(among other diseases), with acute leukemia being the most described cause. From these cases, about 18% are acute lymphoblastic leukemia (ALL), affecting less than 0.5% of patients with this pathology. Its histopathology is marked by the depletion of fat cells in an eosinophilic medium with the presence of amorphous material in at least 50% of the sample. The presence of BMNs in acute leukemia suggests a worse prognosis and lower remission rates. This observational study describes a case report of BMN caused by acute leukemia, with the databeing obtained from the electronic medical record in the UNIVASF University Hospital System (UH).