OBJECTIVE Bone marrow can undergo necrosis for many different causes; malignant causes are reported to be more frequent. METHODS We undertook a 10-year retrospective review of all bone marrow biopsy specimens with bone marrow necrosis at our institution. RESULTS Identified cases represented approximately 0.3% of our bone marrow cases. Most identified bone marrow cases with necrosis were involved by metastatic tumor or hematolymphoid malignancy (90% of total) in relatively equal proportions. In those cases of bone marrow necrosis with hematolymphoid malignancy, lymphoid disease predominated and the necrosis was often seen in the setting of chemotherapy. In metastatic tumor cases, necrosis seemed to enrich in prostate adenocarcinoma and Ewing sarcoma/primitive neuroectodermal tumor; neuroblastoma showed much less necrosis. Ten percent of patients with bone marrow necrosis had no underlying malignancy, and the associated causes varied. CONCLUSIONS The causes of bone marrow necrosis are diverse but should always prompt careful assessment for malignancy and infectious etiology.