An ultra wideband dual-frequency combiner includes a combination port (Port 1), a first port (Port 2) a second port (Port 3), two coaxial resonator band pass filters and two direct current channels. The first direct current channel is connected between the first port (Port 2) and the combination port (Port 1). The second direct current channel is connected between the second port (Port 3) and the combination port (Port 1). One end of the first coaxial resonator hand pass filters (610, 611) is electrically connected with the first port (Port 2) via a first blocking capacitor. One end of the second coaxial resonator hand pass filter (620, 621) is electrically connected with the second port (Port 3) via a second blocking capacitor. The other ends of the first coaxial resonator band pass filter and the second coaxial resonator band pass filter are connected with the combination port (Port 1) via a third blocking capacitor. The blocking capacitors are parameter distributed capacitors.