The invention relates to a phase shifter which comprises a dielectric substrate (4) and substrate coupling circuits (10) arranged on the dielectric substrate (4) and also comprises a sliding unit, wherein the sliding unit can slide relative to the dielectric substrate (4) and comprises sliding sheets (13), a press element (12), a transmission rod (1), screws (2) and nuts (11), the sliding sheets (13) are arranged above the dielectric substrate (4) and provided with a sliding sheet coupling circuit (16), the sliding sheet coupling circuit (16) is coupled with the substrate coupling circuits (10) during the sliding process of the sliding unit, the press element (12) is arranged above the sliding sheets (13), the transmission rod (1) is arranged above the press element (12), the screws and the nuts (11) are used for fixing the transmission rod (1) and the press element (12) on the sliding sheets (13) and making the press element (12) and the sliding sheets (13) tightly pressed on the dielectric substrate (4), the nuts (11) are elastic nuts, and the press element (12) is clamped between the sliding sheets (13) and the elastic nuts. By the phase shifter, the bandwidth is increased, the volume is reduced, and the adjustable inclination range is expanded.