Disclosed is an intelligent vehicle-mounted radar device for reducing polarization loss, wherein, the antenna module includes a dual-polarized antenna, namely, any polarized signal can be measured, and polarization information can be processed and extracted in real time by the polarization digital processor module, the present invention is featured by rapid and real-time. In addition, when the vehicle travels at high speeds, the vehicle-mounted radar device can have certain polarization loss, the present invention can adjust the polarization loss caused by the resonance when the vehicle travels at high speeds, namely, the vehicle speed detection trigger module detects the vehicle speed, when the vehicle speed reaches a first preset value of forming the resonance interference, the polarization control module controls the antenna module to perform polarization calibration, so as to reduce the polarization loss of the intelligent vehicle-mounted radar device, and thus improve the performance of the intelligent vehicle-mounted radar device.