Spinal cord injury (SCI) leads to robust Rho activation at the lesion site. Here, we demonstrate that BA-210, a cell-permeable fusion protein derived from C3 transferase, formulated in fibrin sealant and delivered topically onto the dura matter, diffuses into the spinal cord and inactivates Rho in a dose-dependent manner. Treatment with BA-210 in rats with thoracic spinal cord contusion increased tissue sparing around the lesion area and led to significant improvement of locomotor function. In mice, BA-210 improved functional outcome when treatment was either applied at the time of injury or delayed by 24 h. In both rats and mice, treatment with BA-210 was well tolerated. Rats gained body weight normally, and BA-210 treatment had no impact on the development of allodynia. Inactivating Rho with BA-210 holds promise for treating patients with SCI.