This work presents a new design approach of wideband multilayer Electromagnetic Band Gaps (EBGs) suitable for both on package antenna isolation and switching noise suppression in high speed digital circuits. Depending on the target applications, the design principle is implemented from two conventional types of EBGs in order to improve their initial performance. By stacking multiple dielectric layers with integrated vias in both types of EBGs, it’s possible to achieve dual band performance, to enhance the relative bandwidth of the first band gap and to miniaturize the unit cell. The dispersion diagrams of the multilayer EBGs are proposed and full-wave simulations are performed to validate the antenna isolation and noise suppression bandwidths of the final structures.