Objective To investigate the effect of ADM on spinal cord injury in rat, the related receptor and mechanisms of ADM. Methods In the experiments, male rats received moderate spinal cord contusion injury by modified Allen method. The expression of ADM, ADMR and related iNOS in the normal spinal cord and their changes after SCI were observed, and the effects of ADM on SCBF, spinal cord functional restoration were investigated by ISH, IHC, RIA, LDF, SEP, test of behavioral analysis, etc. Results ADM and ADMR expressed in the neurons of spinal cord anterior horn. After SCI, the expression of iNOS occurred, and the expression of ADM, ADMR and iNOS significantly increased, the trend of the increase is coincident. After intravenous administration, ADM increased the tissues cGMP levels, increase SCBF, relieved the histopathological change, and accelerated the spinal cord functional recovery. Conclusion ADM and ADMR express in rat normal spinal cord. ADM could protect the spinal cord from injury, and the mechanisms may be partly via NO-cGMP signal pathway system.