To observe the clinical effect of reducing yin and reinforcing yang companied with contralateral channel needling in the treatment of dystonia after stroke based on modified Ashworth dystonia spasm scale. Methods: Patients with dystonia after stroke of total 120 cases were divided into treatment group A and control group B, C, D. Treatment group A received reducing yin and reinforcing yang companied with contralateral channel needling treatment, control group B received traditional contralateral channel needling treatment; group C reducing yin and reinforcing yang needling; group D traditional needling. The 30 patients in the four groups also received routine western treatment for dystonia after stroke. Ashworth spasm scale was used to evaluate the efficacy before and after the treatment. Results: The effect of group A was obviously better than that of the other three groups. Conclusion: Reducing yin and reinforcing yang companied with contralateral channel needling has a clear effect in the treatment of dystonia after stroke and can efficiently improve patients’ movement and living capacity.