The aim of this study is to investigate the effects of electroacupuncture, corticosteroid, and combination of two treatments on ambulatory paresis due to spinal cord injury in dogs by comparing therapeutic effects of electroacupuncture and corticosteroid. Spinal cord injury was induced in twenty healthy dogs (2.5~7 kg and 2~4 years) by foreign body insertion which compressed about 25% of spinal cord. There was no conscious proprioception, no extensor postural thrust, and ambulatory. Dogs were divided into four groups according to the treatment; corticosteroid (group A), electroacupuncture (group B), corticosteroid and electroacupuncture (group AB), and control (group C). Neurological examination was performed everyday to evaluate the spinal cord dysfunction until motor functions were returned to normal. Somatosensory evoked potentials (SEPs) were measured for objective and accurate evaluations. The latency in measured potentials was converted into the velocity for the evaluation of spinal cord dysfunctions. Pain perceptions were normal from pre-operation to 5 weeks after operation. Recovery days of conscious proprioception in groups A, B, AB, and C were 21.2+/-8.5 days, 19.8+/-4.3 days, 8.2+/-2.6 days, and 46.6+/-3.7 days, respectively. Recovery days of extensor postural thrust in group A, group B, group AB, and group C were 12.8+/-6.8 days, 13.8+/-4.8 days, 5.4+/-1.8 days, and 38.2+/-4.2 days, respectively. There were no significant differences between group A and group B. However, recovery days of group AB was significantly shorter than that of other groups and that of group C was significantly delayed (p<0.05). Conduction velocities of each group were significantly decreased after induction of spinal cord injury on SEPs (p<0.05) and they showed a tendency to return to normal when motor functions were recovered. According to these results, it was considered that the combination of corticosteroid and electroacupuncture was the most therapeutically effective for ambulatory paresis due to spinal cord injury in dogs.