Abstract: The antenna of X-type flapping wing micro aerial vehicles (MAVs) is usually assembled on the fuselage, resulting in small antenna size and insufficient communication performance. Therefore, flexible electronic technology is studied to design a flapping wing integrated antenna for MAVs, expand the antenna deployment area, and improve the spatial utilization of the aircraft structure. To improve the antenna gain of ultra-thin dielectric substrates, based on the Fabry Perot resonant cavity theory, a 3.50 GHz, 4.68 GHz, and 5.80 GHz tri band microstrip slot antenna is integrated on the lower surface of an X-shaped flapping wing, and an S-shaped metasurface structure is integrated on the upper surface to achieve flexible low profile, multi band, and high gain characteristics. The simulation and test results show that the thickness of the flapping wing integrated Fabry Perot resonant antenna is 0.03mm. Under flapping wing vibration from 5 ° to 90 °, the average gain enhancement at the resonant frequency is 2.08 dB, 3.91 dB, and 2.16 dB, respectively, with an average maximum gain enhancement of 4.59 dB.