This application relates to a phase shifter and a remote electrical tilt antenna including the foregoing phase shifter. The metal strip includes a cavity, a metal strip, a sliding dielectric, and a fastener, where the fastener fastens the metal strip in the cavity, so that a transmission portion of the metal strip is suspended in the cavity, requiring no metal strip to be disposed on a substrate, thereby reducing the signal energy loss of the substrate, decreasing the heat generated due to the signal energy loss, and lowering the requirements of the phase shifter on heat dissipation and temperature resistance of an internal mechanical part.