Abstract: Objective To analyze the effect of thoracic spine scoliosis orthomorphia on stress of lumbar vertebrae using the finite element analysis method. Methods Idiopathic scoliosis was simulated using a 3D finite element model.CT scan was performed for spine from T2 to L5.Structure data of spine from T2 to L5 were extracted.Non-spinal structure data including ribs were deleted and the spinal segments were isolated.The main steps of spine scoliosis orthophoria were simulated and the distribution of stress in lumbar vertebrae was calculated. Results The results of simulation showed that the stress was higher on facet joints of lumbar vertebrae than on other segements in spine scoliosis model.The highest stress value was 68.62MPa which was located at the facets between lumbar vertebrae 2 and 3. Conclusion The stress is higher on lumbar vertebrae.The effect of spinal scoliosis orthomorphia on stress of lumbar vertebrae should take into full consideration during thoracic scoliosis orthomorphia.