PURPOSE: To investigate MR imaging characteristics of the fracture healing process. MATERIALS AND METHODS: We performed MR-pathologic correlation of fractures experimentally produced by the three-point beding system inthe proximal tibias of 24 New Zealand white rabbits. Axial spin echo T1-weighted image(T1WI), T2-weighted image(T2WI) and T1WI after gadopentetate dimeglumine injection were obtained 1-28 days after fracture MR imaging was followed by freezing, sectioning along the MR imaging planes and histopathologic examinations. Changes in MR signal around the fractures were correlated with histopathologic findings. RESULTS: Hematomas and inflammatory tissue around the fractures, noted one day after fracture, showed slightly increased homogeneous signal intensityon T1WI, heterogeneous hyperintensity on T2WI and heterogeneous contrast enhancement. Granulation tissue,cartilage, and immature osteoid, noted 1-4 weeks after fracture, showed iso- or slight hyperintensity on T1WI, hyperintensity on T2WI and contrast enhancement. Hard callus containing ossified osteoid showed hypointensity onboth T1WI and T2WI without contrast enhancement. CONCLUSION: The characteristics of MR signal intensity and contrast enhancing pattern can explain the histopathology of the fracture healing process.