In this paper, the design of Half-Mode Substrate Integrated Waveguide (HMSIW) fed dual frequency microstrip patch antenna has been presented. The proposed antenna is designed using two microstrip patches such that it resonates at two frequencies 9.95 GHz and 11.35 GHz which are used for X-band applications. The HMSIW is excited to generate dominant TE10HM mode. Two patches are used as a radiating elements fed by the open end of HMSIW. The bandwidth at 9.95 GHz is 320 MHz (3.22%) with the return loss of -20 dB and the bandwidth at 11.35 GHz is 580 MHz (5.16%) with the return loss of -30 dB have been achieved. © 2016 IEEE.