A knitted gridding vertebral dilator of Ni-Ti shape memory alloy was designed to be used in the treatment of osteoporosis vertebral compressed fracture. The knitted gridding vertebral dilators with different parameters were knitted and their radial force and elastic modulus were tested; then the best knitted parameters were obtained. Taking into account of the practical application of the vertebral dilators, the structure of both ends of the dilator was improved and an innovative vertebral dilator was obtained which can meet the clinical application needs.