Objective:This paper is to evaluate the efficacy of electro acupuncture XiYan in treating knee osteoarthritis and the modern rehabilitation evaluation  Methods:100 patients with knee osteoarthritis disease were divided randomly into two groups, the treatment group was treated with electro acupuncture for 4 weeks, and the control group was treated with topical diclofenac diethylamine dmulgel for 4 weeks, Lequesne and Vas score were recorded before and after the experiment. Subjects were assessed with isokinetic measurement  Results:After two-week treatment, VAS and Lequesne score of the two groups were better than before(P<0.05), there was no significant difference between the two groups(P>0.05). After four-week treatment, VAS and Lequesne score of the two groups were better than before(P<0.01), as to the VAS score , there was no significant difference between two groups(P>0.05),but the Lequesne score of the treatment group was better than the control group(P<0.05). The rehabilitation value such as PT, PTWB, WF and APT was higher than four weeks before, and the treatment group was batter than the control group(P<0.05)  Conclusion:Electro acupuncture XiYan had advantage in curing KOA, can improve quadriceps femoris muscle strength and improve the stability and the flexibility of the knee.