The present invent discloses an electrically-controlled switching multi-polarization horn antenna, which relates to the technical field of communication antennas. The horn antenna includes a horn antenna body, a polarization controller and a polarization switching apparatus. The horn antenna's control module controls a linear polarization control generation module, a circular polarization control generation module and a polarization selection module to cause the horn antenna to operate in a horizontal polarization mode, a vertical polarization mode, a left-hand circular polarization mode or a right-hand circular polarization mode. The antenna can realize a quick switch between different polarization modes, and the switch is electrically controlled rather than performed by manually replacing the antenna. Using the antenna of the present invent can effectively shorten test time, reduce the number of times replacing antennas by a tester, and more accurately measure characteristics of a device under test in various polarization modes.