We have designed a Metamaterial unit-cell for 9 GHz frequency. Periodic structure was used at 4.25 × 4.25 mm with a thickness of 0.35 mm and giving us the 99.99% of absorbance at 9 GHz in simulated results. We have implemented a rectangular microstrip antenna and loaded it with Metamaterial unit-cells which provided improved results. There were results available for reflection coefficient (s11 parameter) at 9 GHz and also helping for the reduction of the Radar Cross Section of an antenna, which reduced more than 20 dB and not affected its directivity and gain.