A very high efficiency Ultra wide band(UWB) hemispherical dielectric resonator antenna is simulated. The antenna is excited by commonly used feeding technique known as microstrip feeding. The dielectric resonator (DR) is inserted in the vertical edge of the substrate, which covers almost entire UWB bands(3.1 GHz to 10.6 GHz). A high impedance bandwidth of 3.74 GHz to 10.49 GHz is achieved in simulation. Compared to normal hemispherical dielectric resonator antenna, this design shows large volume reduction. A significant result analysis is also given in the paper.