An object of the present invention is to provide a cartilage/bone destruction suppressor which can suppress the destruction of cartilage or bone seen in rheumatoid arthritis, osteoarthritis, bone metastasis of malignant tumor, or the like. The present invention relates to a cartilage or bone destruction suppressor comprising an antibody against folate receptor &bgr; or a complex of the antibody and a biologically or chemically active substance.