Abstract： Objective To determine cell proliferation and nestin expression in the ependyma of adult rat spinal cord after injury. Methods Rat spinal cord injury models were established by aneurysm clip compression, and nestin expression and proliferation of ependymal cells at different times were shown with pathological and immuno-histochemical staining. Results Ependymal cells adjacent to the injured site demonstrated a dramatic increase in nestin expression 24 hours after compression. Proliferating cell nuclear antigen was positive, and significant proliferation was observed after 7 days. Nestin expression was down regulated as time went by. Conclusion Normally quiescent mature ependymal cells appear to revert to an embryonic state in response to spinal cord injury.