In this paper，we build a 3D spinal finite element model including spine (T1-S),pelvic and femur based on human spinal CT scan images. We treat each component of the skeleton as mechanical parts and assemble them based on the normal human body skeleton relations. And mesh model by finite element analysis software Workbench. Then simulate the scoliosis through applying loads on the model, and analysis the influences of lateral force on scoliosis and pelvic tilt when keep the same Cobb angle. Finally we get some value data in conformity with the clinical symptoms, so we can provide some references for orthopaedic surgery for scoliosis.