Abstract: This paper presents the design of a microstrip line fed irregular hexagonal shaped monopole antenna. The antenna consists of a sliced semi-circular ground plane with a square slit below the feed line which exhibits an Ultra Wide Band (UWB) of 7.5GHz. A frequency notch band (5.1GHz -5.57GHz) is obtained by introducing 'U' shaped slot on to the proposed antenna. The proposed monopole is fabricated, measured for reflection coefficient, radiation pattern and peak gain to validate the performance of the antenna.