A novel Fabry-Perot Resonant Antenna(FPRA) is proposed，which utilizes a multi-layer dielectric superstrate to enhance its gain and aperture efficiency. This multilayer superstrate is fabricated by assembling several dielectric plates with different thicknesses and areas. This FPRA works at 5.8 GHz，employs a patch antenna as its feed，and assembles three Teflon plates with different thicknesses(1 mm,1 mm and 1.5 mm) and diameters(160 mm,130 mm and 120 mm) but a same relative permittivity of 16 to be its superstrate. A prototype is fabricated and measured. The measurement results agree well with the simulation ones, and show，in comparison with the commonly adopted single-layer superstrate，the proposed multi-layer superstrate improves the F–P resonant antenna’s gain from 18.2 dBi to 19.1 dBi at 5.8 GHz，correspondingly enhances the aperture efficiency from 70.02% to 86.14%, additionally，slightly increases the antenna’s |S11|<-10 dB impedance bandwidth and 3 dB gain bandwidth，which are 8.19% and 11.90% respectively.