A novel UWB antenna yields an impendence bandwidth of 2.0~10.6 GHz is designed in this paper, supposed to fulfill many requirements such as small size, wide working bandwidth, ominidirectional radiation patterns. A novel, feasibility method used for bandnotched characteristics is demonstrated and the equivalent circuit for this method is proposed. Simulated and measured results all show that the UWB antenna yields an impendence bandwidth of 2.0~10.6 GHz by defining VSWR 2. Based on this method, a extremely narrow notch band at 5.0~5.90 GHz is realized by adding a patch connected with the radiation patch by a via hole, covering the operating band of WLAN((5.125~5.85 GHz). And it improves the quality of WLAN communication links in UWB environment, realizing spectrum compatibility.