The invention provides a base station, an antenna, and a phase shifting device, wherein the phase shifting device includes a fixed dielectric plate, a movable dielectric plate, and a limiting member; the pivoting end of the movable dielectric plate can be pivotally mounted on the fixed dielectric plate, A fixed transmission line is arranged on the fixed medium plate, and the fixed transmission line is extended along the rotation path of the free end of the movable medium plate, and the two ends of the fixed transmission line respectively form signal output ports; at least one surface of the movable medium plate is provided with a movable transmission line, the movable The transmission line is electrically connected to the signal input port on the fixed medium plate; the limiter is arranged parallel to the fixed medium plate along the extension path of the fixed transmission line, so as to jointly define with the fixed transmission line for the free end of the movable medium plate to perform rotational movement Arc-shaped slits for phase shifting. The phase shifting device of the present invention has a compact overall structure, is easy to install, occupies a small space, and has good phase shifting performance, and is especially suitable for 5G Mass i ve MI MO electric tuning antennas.