The invention discloses an antifreeze system for an air inlet wellbore of an underground mine in a high-cold region. The antifreeze system is composed of a preheating unit (15), an air curtain unit (18), an annular jet air vent (19), a fan device, an air door, sensors and a PLC control system (14) in a combined mode; the preheating unit (15) is arranged on the wellhead earth surface of an air inlet well (2), the air curtain unit (18) is arranged on the wellhead earth surface of an auxiliary well (1); the annular jet air vent (19) is arranged in the wellbore of the auxiliary well (1); and the PLC control system (14) is connected with all the sensors, receives data collected by all the sensors and adjusts and controls operation of the preheating unit (15), the air curtain unit (18), the fanand the air door. According to the antifreeze system, normal ventilation and inverted ventilation state freezing resisting of the air inlet wellbore at the day and night time periods can be achieved according to the characteristic that the air flowing direction of a ventilation system is changed due to the change of the day and night temperature difference of the underground mine in the high-coldregion.