The invention discloses a method for repairing a road by accurately filling road base damages with high polymer. The method comprises the following steps: S1, detecting the position of a cavity below an air road through ultrasonic waves; S2, drilling through repair equipment according to the position of the cavity; S3, pre-setting a pressure intensity value for the repair equipment, introducing an isolating film into the cavity through the repair equipment, and charging gas into the isolating film through the repair equipment, so that the preset pressure intensity value is achieved in the isolating film; S4, discharging the gas in the isolating film and taking out the isolating film, and feeding the isolating film into the cavity through space regulating equipment; S5, calculating the volume of the cavity according to the amount of the gas charged into the isolating film, and grouting into the isolating film according to the volume of the cavity; and S6, regulating volume of space, occupied in the cavity, of the space regulating equipment according to the pressure on the space regulating equipment. The method can be used for simply, conveniently and quickly filling the cavity below the road with a proper amount of high polymer.