Objective To evaluate the effect of the plasma treated PLGA nerve conduits seeded BMSCs on repairing SD rat sciatic nerve defects. Methods BMSCs were acquired from 30 newborn SD rats. After ampl ified and passaged for 3 times, PLGA nerve conduits were prepared and some of them were treated with plasma. A 1-cm-length sciatic nerve defect wasmade in 30 4-week-old SD rats, then they were randomly divided into 3 groups for three different nerve defects reconstruction methods (n=10). In the experimental group, defect was repaired by plasma treatment and PGLA nerve conduits seeded with BMSCs; in the control group, by normal PLGA nerve conduits seeded with BMSCs; and in the autologous group, by autologous nerve. At 6 weeks after the surgery, the dynamic walking pattern was recorded and the sciatic function index (SFI) was calculated; the electrophysiological test was taken; the gastrocnemius wet weight recovery rate was calculated; and the image analysis of regenerated nerve was made. Results All rats survived after the surgery and l ived to the end of the experiment. At 6 weeks after the surgery, the dynamic walking pattern of the experimental group and autologous group was better than that of the control group. The SFI value of the experimental, control and autologous groups was —51.02 ± 6.54, —58.73 ± 7.87 and —48.73 ± 3.95, respectively, showing statistically significant differences among the experimental group, control group and autologous group (P lt; 0.05). The results of the motor nerve conduction velocity and wave ampl itude showed that there were statistically significant differences between the experimental group and the control group (P lt; 0.05), and between the control group and the autologous group (Plt; 0.01); but no significant difference between the experimental group and autologous group(Pgt; 0.05); The gastrocnemius wet weight recovery rate of the experimental, control and autologous groups was 56.13% ± 4.27%, 43.14% ± 6.52%, 59.47% ± 3.85%, respectively; showing statistically significant differences among experimental group, control group and autologous group (P lt; 0.05). The density, diameter of regenerated nerve fiber as well as neural sheath thickness of the experimental group were all higher than those of the control group (P lt; 0.05) and lower than those of the autologous nerve group (P lt; 0.05); there was significant difference between the control group and the autologous group (P lt; 0.01). Conclusion Plasma treated PLGA nerve conduits seeded with BMSCs can effectively repair sciatic nerve defects and provide a new strategy for the development of tissue engineered nerve to repair the peripheral nerve defects.