A filtering antenna element and a dual-band filtering antenna array using filtering antenna elements for mutual coupling suppression have been disclosed. The filtering antenna element comprises a feeding element, a sub-substrate, a sup-substrate and an air gap between the sub-substrate and the sup-substrate. A stacked patch is fabricated on a top surface of the sub-substrate, a driven patch and a ground plane are fabricated on a top surface and a bottom surface of the sub-substrate. An asymmetric E-slot is arranged on the driven patch and a shorting pin is inserted into the sub-substrate for generating radiation nulls in stopbands. The dual-band filtering antenna array is compact and needs no feeding network with an isolation of 35 dB, and is suitable for potential base station applications.