The invention discloses a hydraulic walking type percussion reverse circulation slot repairing machine, belonging to the technical field of well drilling equipment. A chassis is arranged below a frame and connected with the frame through a revolving support, a guide frame comprises a columnar pile, guide tracks and a connecting rod, the bottom of a mast is articulated at the front of the frame, the two ends of a variable amplitude oil cylinder are respectively connected on the mast and the frame, a gooseneck boom is arranged at the top end of the mast, the guide tracks are arranged on the left side surface and right side surface of the mast, the guide frame is positioned in front of the mast and connected with the mast, the top end of the guide frame is connected with an auxiliary winch steel wire rope, the other end of the auxiliary winch steel wire rope is connected onto an auxiliary winch through a pulley on the gooseneck boom, a percussion bit is positioned in front of the guide frame and clamped on the guide tracks through guide claws, the top end of the percussion bit is connected with a main winch steel wire rope, the other end of the main winch steel wire rope is connected onto a main winch through the pulley on the gooseneck boom, and an air compressor is connected with a curved pipe at the lower part of the columnar pile through an air conveying pipe. The hydraulic walking type percussion reverse circulation slot repairing machine can flatly enlarge and excavate the edges of a channel, ensure that the bottom of the channel is through and simultaneously remove the soil and rock at the bottom of the channel during repair of the channel.