Abstarct: In this thesis, a novel method is presented for improving isolation and enhancing the performance of a two-port MIMO antenna baxsed on an Epsilon-Negative (ENG) mextamaterial unit cell. In the proposed approach, the ENG mextamaterial cell is placed vertically between the antenna elements and acts as a mutual coupling reduction structure, without the need for complex decoupling networks or major modifications to the antenna geometry. The dimensions of the microstrip patch MIMO antenna are 1.1λL × 0.7λL × 0.16λL, where λL represents the wavelength corresponding to the antenna’s resonant frequency. After loading the ENG unit cell, the isolation is increased up to 37 dB. The operating bandwidth of the MIMO system ranges from 5.1 to 5.22 GHz.