Abstract: A waveguide polarization tracker is proposed based on the principle of polarization synthesis. It is mainly composed of polarization tracker and motor control structure. The polarization tracker consists of a 3 dB directional coupler and an adjustable reflective phase shifter. The adjustable reflective phase shifter adopts the load terminal of the mountain-shaped choke structure, which can effectively prevent energy leakage and realize flexible regulation of the output phase. The motor control structure consists of a drive motor, a sliding device and a transmission device. The structure adopts a planar integrated design to achieve continuous linear polarization tracking. The experimental results show that the return loss of the designed waveguide polarization tracker is better than 20 dB, the isolation of the output port is higher than 18 dB, and the transmission loss is lower than 0.3 dB in the range of 13.5 GHz~14.5 GHz. The synthesized linear polarization angle can be continuously scanned in the range of 0°~180°, and the adjustment error of polarization angle at different frequencies is no more than 2°.