Abstract: Two designed of Ultra-Wide Band (UWB) monopole antenna with/without Electromagnetic Band Gap (MEBG) mushroom structure has been designed and analyzed. EBG structure is used in UWB monopole antenna to enhance the gain and the bandwidth as well, several main parameters of the proposed antenna are discussed such as return loos, gain, radiation pattern. First design of monopole antenna gave the bandwidth without EBG of 8.069 GHz (2.77-10.84 Ghz) while the maximum gain is 4.4 dB. Whereas second design with EBG gives wide huge bandwidth of 23.33 GHz (2.67-26 GHz) and higher maximum gain 5.8 dB. The highest impedance bandwidth attained is 161% considers VSWR 2:1. The proposed antenna will serve different applications such as Bluetooth, cellular systems and satellite communication and 5 G. The greater bandwidth also offers the antenna low mutual coupling rather than the antenna without EBG. FR4 substrate is used here with comparative permittivity 4.4. At the end of this study, physical model and measured results are presented and the measured results well match with the simulations.