Idiopathic scoliosis is a spinal deformity without clear etiology, and biomechanical factors play an important role in its pathogenesis and treatment. The spatial load inequality of the spine and its accessories, the unbalanced development of the vertebral body, and the pedestal instability caused by pelvic inclination and rotation have important influences on the development of idiopathic scoliosis. Both brace therapy and pedicle screw-rod system therapy are based on biomechanical characteristics and are continuously progressing. This review sums up the research advances on biomechanical characteristics of idiopathic scoliosis and its therapy strategy in recent years.