The invention discloses a lower limb body position fixing rack, which comprises a support framework and a vertical framework, wherein the vertical framework is arranged at one end of the support framework; the support framework is of a cuboid framework structure; slide grooves are respectively formed in two long side frames of the top surface of the support framework; a silicon rubber pad is arranged on each slide groove and can freely slide along the two long side frames on the top surface of the support framework through the slide grooves; and a nylon hook belt and a nylon loop belt of a nylon hasp are also arranged on the two long side frames of the support framework, and can be mutually matched for fixation. The lower limb body position fixing rack provided by the invention has the advantages that the weight is light; the appearance is ingenious; the use is convenient and fast; the limb biomechanics requirements can be met; the body position can be regulated at the proper time for many times; the hamstring tendon contracture is prevented; and the walking after the healing is convenient. The fixation is firmer and more reliable; the blood circulation influence due to excessive injury to the outer skin flaps cannot occur even when external force factors exist; the skin flap compression is effectively prevented; and the skin flap blood circulation can be conveniently observed. An electric baking lamp is additionally arranged on the fixing frame, so that the postoperative heat insulation effect can be achieved.