A dielectric filter , comprising: a cavity , wherein the cavity comprises an accommodating cavity and a cavity wall surrounding the accommodating cavity ; a resonator , wherein the resonator is disposed inside the accommodating cavity , the resonator comprises a support medium and a main medium , the support medium is disposed on a bottom wall of the accommodating cavity , and the main medium is disposed on the support medium ; a cover plate , wherein the cover plate covers the cavity to close the accommodating cavity ; and a connecting rib , wherein the connecting rib is accommodated in the accommodating cavity , and is disposed on a radiation plane formed between a radiation radiated from a center axis (I) of the resonator onto the cavity wall and the center axis (I) of the resonator , wherein a shortest distance between the connecting rib and the main medium is greater than a preset value; wherein the connecting rib comprises a support part and a first extending part that is formed by extending a first end of the support part in a direction away from the support part , and shortest distances between the support part and the main medium and between the first extending part and the main medium are greater than the preset value; characterized in that the connecting rib further comprises a second extending part , the second extending part is formed by extending, in a direction away from the support part , a second end that is of the support part and that is opposite to the first end, wherein a shortest distance between the second extending part and the main medium is greater than the preset value. a cavity , wherein the cavity comprises an accommodating cavity and a cavity wall surrounding the accommodating cavity ; a resonator , wherein the resonator is disposed inside the accommodating cavity , the resonator comprises a support medium and a main medium , the support medium is disposed on a bottom wall of the accommodating cavity , and the main medium is disposed on the support medium ; a cover plate , wherein the cover plate covers the cavity to close the accommodating cavity ; and a connecting rib , wherein the connecting rib is accommodated in the accommodating cavity , and is disposed on a radiation plane formed between a radiation radiated from a center axis (I) of the resonator onto the cavity wall and the center axis (I) of the resonator , wherein a shortest distance between the connecting rib and the main medium is greater than a preset value; wherein the connecting rib comprises a support part and a first extending part that is formed by extending a first end of the support part in a direction away from the support part , and shortest distances between the support part and the main medium and between the first extending part and the main medium are greater than the preset value; characterized in that the connecting rib further comprises a second extending part , the second extending part is formed by extending, in a direction away from the support part , a second end that is of the support part and that is opposite to the first end, wherein a shortest distance between the second extending part and the main medium is greater than the preset value. <EOS>