The secondary electron emission yields of materials depend on the geometries of their surface structures.In this paper,a method of depositing vertical graphene nanosheet (VGN) on the surface of the material is proposed,and the secondary electron emission (SEE) characteristics for the VGN structure are studied.The COMSOL simulation and the scanning electron microscope (SEM) image analysis are carried out to study the secondary electron yield (SEY).The effect of aspect ratio and packing density of VGN on SEY under normal incident condition are studied.The results show that the VGN structure has a good effect on suppressing SEE.