Objective:To discuss the imaging features of bone infarction. Methods:Radiography,CT and MRI were performed in 13 patients with 44 bone infarctions. The imaging findings were analyzed to classify the lesions into acute,subacute and chronic stages. Results:The lesions mainly involved in the distant segments of femur and proximal segments of tibia on both sides. Bone infarction appeared negative or atypical patchy calcification on both radiography and CT. In acute stage, the center area of lesions presented normal bone marrow or slight edema or hemorrhage on MRI. In subacute stage,the infarction was manifested as iso-or slight low-signal on T1WI and iso- or slight high-signal on T2WI in center areas. A low-signal zone around was separated from the normal marrow with linear T1 low-signal and T2 high-signal in both acute and subacute stages. In chronic stage,the lesion was characterized by low-signal on both T1WI and T2WI,indicating the formation of fibrosis and dystrophic calcification due to the replacement of necrotic tissue by granulation and fibrous tissue. Conclusion:MRI is a good method of early detection and correct diagnosis due to its high sensitivity and characteristic imaging features.