In the thesis, we propose an intelligent metamaterial to reduce the specific absorption rate (SAR) of cellular phone to phantom. We call our design intelligent metamaterial because it will not affect the antenna performance greatly. When the antenna is close to the phantom, the metamaterial acts like a stopband filter, thus reducing the SAR. We design a small metamaterial cell resonating at GSM 900 band, having 2 cm x 2cm x 0.4 cm in size. We use three cells to shield the PIFA antenna and the SAR is reduced by 29.12 % at a distance of 15 mm away from the phantom. Then we design a metamaterial cell having 1 cm x 1.95 cm x 0.4 cm in size,operating in GSM 1800 band. We use four cells to shield the PIFA antenna and the SAR reduced by 40.2 % at a distance of 15 mm away from the phantom. We also propose a dualband (GSM 900/1800) metamaterial having 2 cm x 4 cm x 0.8 cm in size. We use nine metamaterial cells to shield the dualband antenna and the ground¡Athe SAR reduced by 25 % at 900 MHz and 32.6 % at 1800 MHz at a distance of 15 mm away from the phantom.