Abstract:A kind of lefthanded material (LHM) with the crosscoupled structure is designed in this work. A new type of ultra wide band (UWB) notch filter constructed by the proposed LHM has a passband of 3.16~11.84 GHz and a stopband of 7.01~8.56 GHz. Aiming at the problems of difficult design, large size and low filtering performance existing in the planar antenna, an UWB filtering antenna based on LHM has been realized through loading the LHM filter onto two simplestructure and easytofabrication planar antennas. Comparing with the conventional planar antenna, the proposed filter antenna has both radiation and filtering functions. The HFSS software simulation and calculation show that the filter antenna operates in the ultra wide band, the return loss at X band notch is up to -1.30 dB, which can realize the integration and miniaturization design of UWB antenna.