A phase shifter may include a cavity body, and a fixed circuit board and a phase shift unit that are located inside the cavity body, and the phase shift unit being capable of moving relative to the fixed circuit board. A power division circuit is disposed on the fixed circuit board. The power division circuit includes an input end, a main feeder, a node, at least two output ends, a filtering stub, and at least two output circuits. The main feeder is electrically connected between the input end and the node. The filtering stub is electrically connected to the main feeder, and the filtering stub is in an open-circuit state. The at least two output circuits are respectively electrically connected between the node and the at least two output ends. The phase shift unit is disposed in correspondence with the at least two output circuits.