Purpose: This study was designed to investigate the effects of treadmill exercise on functional recovery after rat with experimental SCI. Methods: SCI was induced by the NYU-spinal cord impactor(NYU, USA) dropped a weight of 10 gm after laminectomy. Experimental groups were divided into the Group I (normal), Group II (control) and Group III(treadmill exercise). After 2 days of the operation, 24 rats(group II, III) were trained to walk on treadmill for 21 days twice/day, 15 min/session. After operation, rats were tested at modified Tarlov scale at 1, 2, 3, 4 days with divided into 2 groups, and Motor behavior test(BBB locomotor rating scale, Grid walking test, Narrow beam crossing test, Modified inclined plane test) was examined at 1, 3, 7, 14 and 21 days. Histopathological study were performed at 1. 3, 7, 14 and 21 days by H&E, Luxol Fast Blue staining were same times. Results: After SCI an improvement of motor behavior was shown group II, III. The motor behavior test of group Ill showed considerable improvement until 14 days. Conclusion: These results suggest that treadmill exercise treatment can playa role in facilitating recovery of locomotion following spinal cord injury.