Abstract: A uniform mushroom-like electromagnetic band-gap (EBG) structure can realize only one surface-wave suppression bandgap. Hence, two kinds of units with different parameters mushroom-like EBG structures are cascaded to realize the dual-band or broadband surface-wave suppression bandgap. This paper presents a dual-band EBG structure using cascaded mushroom-like structures with different patch sizes. Two kinds of uniform EBG structures are used to produce two suppression surface-wave bandgaps covering the two operating frequency respectively. The cascaded structure is integrated between slotted microstrip antennas. Simulation and experimental results show that the cascaded structure can suppress the surface-wave effectively and decrease the mutual coupling of the two operating frequencies at t