A compact Ultra WideBand (UWB) antenna with band-notched characteristic is presented in this paper. It has compact size of 30 mm x 31mm and has ultra wide band operation. A 'C' shaped slot was introduced to achieve band notch function from 4.8 GHz to 6 GHz to avoid interference from WLAN. The proposed antenna has ultra wide band frequency range from 3 GHz to 11.5 GHz for return loss below -10 dB, except for frequency stop band from 5 GHz to 6 GHz. Details of antenna are presented with parametric study for Ultra Wideband Applications.