In this paper, band notch characteristics with reduced ground plane effect in Ultra wide band antenna is proposed. This newly simulated structure is proposed for fabrication. The antenna is suitable for operating frequency range in UWB band and it is shown that return loss of this antenna at four resonant frequencies at 2.5GHz, 5.5GHz 8.5GHz and 10.5 is better than -10 dB. The VSWR obtained is less than 2.0 of this multiband antenna with the compact size and large bandwidth. The return loss values of first band is -16.1 dB second bands is -45 dB third band is -24dB and fourth band is -20dB with radiation efficiency is 82 % and directivity 3.65 dB. The measured results are also calculated with Vector Network analyzer. In addition parametric study of various parameters of proposed antenna will be able to provide antenna engineers with more design information.