PROBLEM TO BE SOLVED: To provide a semilunar plate regeneration backing material in which in regeneration therapy of a semilunar plate, charging is performed in a defective part of the semilunar plate of a knee arthrosis, thereby accelerating regeneration of the semilunar plate.SOLUTION: A semilunar plate regeneration backing material in which in regeneration therapy of a semilunar plate, charging is performed in a defective part of the semilunar plate of a knee arthrosis, thereby accelerating regeneration of the semilunar plate, includes a crosslink collagen sponge and knee lid lower fat body, the crosslink collagen sponge having a thickness of 1-30 mm, and an average pore diameter of 1-1,000 &mum.