A 2D/3D switching apparatus includes a switching layer that includes a cylindrical lens grating and a cavity defined by a cylindrical curved surface of the cylindrical lens grating and a cover, a container for storing a transparent liquid that has a refractive index equal to a refractive index of a material of the cylindrical lens grating, and a vacuum pump respectively connected with the cavity of the switching layer and the container. The vacuum pump injects the transparent liquid from the container to the cavity of the switching layer, or injects the transparent liquid from the cavity to the container.