In this paper, Genetic Algorithm (GA) optimization technique is adopted to design an UWB Monopole antenna operating in the 3.1-10.6 GHz band. The main goal of the algorithm is to minimize the return loss below -10 dB for better impedance matching. The designed antenna was miniaturized to (47×47 mm2) and simulated on low cost FR4 substrate. The algorithm implementation was achieved by MATLAB™ software and the electromagnetic simulation was carried out based on the Finite Difference Time Domain (FDTD) technique by CST Microwave Studio software. Finite Element Method (FEM) employed by the frequency domain electromagnetic software HFSS was used to verify the results. The simulation reveals UWB impedance matching exceeding 10 GHz with omni-directional radiation pattern.