The utility model discloses a lower limb operation frame, which belongs to a medical instrument and comprises a frame body, a supporting plate and a hydraulic extension device. The supporting plate comprises a front supporting plate, a back supporting plate and a lower supporting plate. Sliding grooves are symmetrically arranged at the lefts sides of a front and a back side frame of the frame body. One end of the front supporting plate is connected with a left supporting plate shaft which is arranged in one sliding groove. One end of the back supporting plate is connected with a right supporting plate shaft which is fixed with the frame body. Two sides of the front supporting plate and two sides of the back supporting plate are provided with slots, and the top parts of the slots are respectively provided with fixing bolts. Two ends of the lower supporting plate are respectively inserted into the lower parts of the front and the back supporting plates, and the middle of the lower supporting plate is connected by a connecting shaft. The hydraulic extension device comprises a hydraulic pump, a center shaft and an extensible hydraulic rod. An operating button is connected with the hydraulic pump which is connected with a power wire port. The lower limb operation frame has the advantages of safe and easy operation, stable hurt limb placement, manpower and materials saving, operation time shortening, pollution possibility reduction, convenient use, and the like.