The present invention relates to a composition for preventing or treating spinal cord injury, the composition containing poly-sialylated neural cell adhesion molecule (PSA-NCAM) positive neural cells as an active ingredient. The PSA-NCAM positive neural cells (e.g., PSA-NCAM positive neural precursor cells) of the present invention, when transplanted into spinal cord injury animal models, are differentiated into astrocytes, oligodendrocytes, or neurons (NeuN positive cells), which are three types of important cells constituting neural tissues, and exhibiting a behavior improvement effect due to the recovery of neural functions and the restoration of the injured spinal cord tissues. Thus, the cells can be used for a composition for preventing, alleviating, or treating spinal cord injury.
