A simple and compact ultra-wideband (UWB) printed planar monopole antenna with dual narrow band-notched characteristics is proposed. The band notches are realised by employing a U-slot defected ground structure in the ground plane on the back side and etching a split ring slot in the radiation patch on the front side, and dual narrow rejected filtering properties in the lower WLAN band and upper WLAN band are achieved. Experimental results show that the presented antenna, with a compact size of 30×34 mm, has a wide bandwdith from 2.8 to 12 GHz with dual band notches. Moreover, the antenna has good omnidirectional radiation patterns in the H-plane.