Abstract：A leg correction medical instrument using an air pressure device for translocation comprises a substrate (3) and a vertical stand column (95) fixedly connected with the substrate. A sliding rail (89) is arranged on the substrate (3) and used for being in sliding fit with a sliding correction assembly. The sliding correction assembly comprises a mounting plate and a vibration plate (91) in sliding fit with the mounting plate, a cam rotating shaft is arranged on the mounting plate, a vertical bevel gear (86) is arranged at the upper end of the cam rotating shaft, cams (87) are arranged in the middle and the lower end of the cam rotating shaft respectively and used for being jointed with the vibration plate (91) to generate vibration in the cam rotating process, a drive box is arranged at the top end of the mounting plate, a left horizontal shaft is arranged at the left end of the drive box, a horizontal bevel gear (85) is arranged on the left horizontal shaft and used for being meshed with the vertical bevel gear (86), and a horizontal screw rod (98) is arranged between the right end of the drive box and the vertical stand column (95).