Abstract: In order to obtain a radiation pattern reconfigurable antenna operating in the same frequency, a radiationpattern reconfigurable printed dipole antenna is proposed in this paper. By changing the states of the switches, the antennacan be operated as a monopole antenna with omnidirectional pattern or a dipole antenna with reflector which can radiationdirectional pattern. The effects of the antenna’s dimension on the antenna performance are analyzed using Ansoft HFSS10.0,and then the optimized parameters are presented. In the simulated results, the operation bands at 2.34～2.64GHz, the antenna has an omnidirectional pattern at switches ‘off’ state, it has a directional pattern at the switches ‘on’ state. The peak gain is6.7dB and 3.1dB at 2.45GHz.