Provided in the present invention is a miniaturized antenna, comprising a reflecting plate, a first radiation unit, and a first phase shifter, wherein the first radiation unit and the first phase shifter are respectively arranged on two opposite surfaces of the reflecting plate, the first radiation unit comprises a radiation arm and a feed piece used for feeding the radiation arm, the first phase shifter comprises a cavity and a phase-shifting circuit disposed within the cavity, the feed piece passes through the reflecting plate and penetrates into the cavity to connect to the phase-shifting circuit, and a gap is provided between the cavity and the reflecting plate. In the miniaturized antenna provided by the present invention, the first radiation unit is directly connected to the first phase shifter without external connection to a coaxial cable, which can effectively simplify the assembly process, and can also prevent dielectric loss caused by the coaxial cable and increase antenna gain. Second, since there is a gap between the cavity and the reflecting plate, the coupling effect between different frequency bands can be reduced, so that the antenna can be configured with a radiation unit having multiple frequency bands, thereby improving the applicability.