▎ 摘　　要

As the potential-wide applications in valleytronic devices, the valleytronics, especially the valley polarization in graphene, has attracted much attentions. Thus, in the present work, we study the effect of the applied bias on the valley polarization in a magnetic-strained graphene, which has been not studied as we know. Concretely, we analyze the dependence of the valley polarization on the magnitude, the position, and the width of the applied bias, and obtain the large valley polarization in such a graphene nanostructure which can be easily controlled by the applied bias. This study can promote the realization of the applied bias-tunable valleytronic devices.