The invention provides a high out-of-band rejection cavity filter antenna array which comprises a dielectric substrate, a first metal layer and a second metal layer. The first metal layer and the second metal layer are arranged on the upper surface and the lower surface of the dielectric substrate respectively, multiple first metallized through holes are formed in the dielectric substrate, the first metal layer and the second metal layer and the first metallized through holes surround to form a first rectangular resonant cavity and two second rectangular resonant cavities symmetric according to the first rectangular resonant cavity, the second rectangular resonant cavities directly face each other and are arranged closely to two sides of the first resonant cavity, each second rectangular resonant cavity and the first rectangular resonant cavity are in coupled cascading through a first coupling opening arranged therebetween, two radiation gaps used for radiating signals are arranged at positions, corresponding to the second rectangular resonant cavity, of the first metal layer, and an input unit used for inputting signals to the first rectangular resonant cavity is arranged on the dielectric substrate. The high out-of-band rejection cavity filter antenna array has the advantage of high rejection capability to electromagnetic wave radiation out of a passband.