In recent years, orbital angular momentum has been a hot research topic in wireless communication. In this paper, an orbital angular momentum antenna based on dielectric resonator is proposed by combining orbital angular momentum with millimeter wave technology. The equivalent model of the antenna is established, the theoretical expression of its radiation field is derived, and the effect of the dielectric resonator radius on the vortex wave electromagnetic wave mode is discussed. The simulation results show that the antenna has four resonance points in band and can generate vortex electromagnetic waves with mode respectively. In addition, the antenna has a compact structure, low cost, good gain, high antenna efficiency, and the generated vortex electromagnetic waves of each mode have good rotational properties, which can obtain a strong anti-interference capability and provide some practical significance for the application of orbital angular momentum in the millimeter wave band.