Electric field stimulation (EFS) can effectively inhibit local Ca2+ influx and secondary injury after spinal cord injury (SCI). However, after the EFS, the Ca2+ in the injured spinal cord restarts and subsequent biochemical reactions are stimulated, which affect the long-term effect of EFS. Polyethylene glycol (PEG) is a hydrophilic polymer material that can promote cell membrane fusion and repair damaged cell membranes. This article aims to study the combined effects of EFS and PEG on the treatment of SCI. Sprague-Dawley (SD) rats were subjected to SCI and then divided into control group (no treatment, n = 10), EFS group (EFS for 30 min, n = 10), PEG group (covered with 50% PEG gelatin sponge for 5 min, n = 10) and combination group (combined treatment of EFS and PEG, n = 10). The measurement of motor evoked potential (MEP), the motor behavior score and spinal cord section fast blue staining were performed at different times after SCI. Eight weeks after the operation, the results showed that the latency difference of MEP, the amplitude difference of MEP and the ratio of cavity area of spinal cords in the combination group were significantly lower than those of the control group, EFS group and PEG group. The motor function score and the ratio of residual nerve tissue area in the spinal cords of the combination group were significantly higher than those in the control group, EFS group and PEG group. The results suggest that the combined treatment can reduce the pathological damage and promote the recovery of motor function in rats after SCI, and the therapeutic effects are significantly better than those of EFS and PEG alone.