Abstract-In this work, an E-shape Defected Ground Structure (DGS) is achieved to reduce the mutual coupling between two nearby microstrip antennas up to 47% (from 0.064 to 0.03). Both antennas radiate in the same frequency band of 10 GHz. The technique is based on a wall integrating periodic structure permitting the absorption of the electromagnetic field. By using this structure, it was possible to achieve a 20 dB reduction in the insertion loss S 21 between the two microstrip patch antennas with center-to-center distance of 0.45λ 0 (λ 0 is the free-space wavelength). The obtained coupling coefficient demonstrates that there is a good isolation between the two antennas. EM solver, simulating the reflection and transmission coefficients of the designed antenna arrays, achieves the reduction of the mutual coupling. The simulated results are verified by measuring the fabricated prototypes.