Abstract: A dual-polarization omnidirectional antenna includes a reflecting base plate, a radiating oscillator, outputting coaxial cables, RF connectors, a metallic supporting pillar and a T-shaped probe. The radiating oscillator has an upper layer provided with a one-to-two feed dividing network and a lower layer provided with a round patch; the T-shaped probe is welded with the round patch. A mixing ring is arranged on the reflecting base plate; two RF connectors are respectively connected with a first port and a second port of the mixing ring; an inner conductor of a first outputting coaxial cable has a first end connected with the feed dividing network and a second end connected with a third port of the mixing ring; an inner conductor of another outputting coaxial cable has a first end connected with the T-shaped probe and a second end connected with a fourth port of the mixing ring.