Background and Aim: There are several reports regarding anti-inflammatory and tissue repair properties of the plant Achillea, but neuroprotective role of ethanolic extract of Achillea millefolium has not been studied after peripheral nerve injury. Therefore, the purpose of the present study was to assess neuroprotective effects .of Achillea millefolium ethanolic extract on the spinal cord alpha motor neuons after sciatic nerve compression in male rats. Materials and Methods: In this experimental study 30 male Wistar rats each weighing 200-250g were chosen and were randomly divided into 5 equal groups including control, compressed, and three compressed groups plus intraperitoneal injection of Achillea millefolium ethanolic extract with the concentration of 50, 75, and 100 mg/kg; once a week for three weeks. . Sciatic nerve compression in these four groups . was done using hematostatic forceps for 60 seconds. After 28 days, L4, L5,S1, and S3 of the spinal cord were sampled using perfusion method. Statistical analysis of the obtained data was done by means of one-way Anova and Tukey post- hoc test using SPSS( version 19 ) at the significant level of P<0.05. Results: It was found that α-motor neurons density in the compression group (666.6±39.17) significantly decreased compared to the control group (1754±34.22) ;P <0.001. Neural density in the groups treated with ethanolic extract, i.e. 50 mg/kg .,75 mg/kg, .and.100 mg/kg was 1236±69.72.,.1444.3±39.17,.and 1546.3±57.39 respectively ;which showed a significant increase compared to the compression group (P<0.01). Conclusion: Ethanolic extract of Achillea millefolium had a neuroprotective effect after sciatic nerve compression. Presumably, this is due to antioxidant and anti-inflammatory compounds in the plant.