The invention relates to a self-adaptive multi-waveband integrated impedance matching network broadband horn antenna. The broadband horn antenna comprises a control foundation support, a power divider, a frequency detection device, a numerical-control attenuator, a numerical-control phase shifter, a radio-frequency signal receiving-transmitting device, a data processing circuit, double-ridged waveguides and a guide corrugated bell mouth, wherein the data processing circuit is respectively electrically connected with the power divider, the frequency detection device, the numerical-control attenuator, the numerical-control phase shifter, the radio-frequency signal receiving-transmitting device, the double-ridged waveguide and the guide corrugated bell mouth; the guide corrugated bell mouth comprises a positioning base plate, an electromagnetic impedance winding, a reflection adjusting plate and a positioning frame; at least four double-ridged waveguides are uniformly distributed on the inner surface of the positioning frame of the guide corrugated bell mouth along the axis of the guide corrugated bell mouth. By adopting the self-adaptive multi-waveband integration impedance matching network broadband horn antenna, on one hand, the application flexibility and reliability of the double-ridged antenna can be effectively improved, on the other hand, the adaptive adjustment can be automatically performed according to the frequency variation of a communication signal, an electromagnetic noise wave can be effectively filtered, and the specific electromagnetic signal can be enhanced.