Abstract: Computer image processing technology is commonly used in clinical diagnoses of lumbar vertebrae problems and in medical research to segment single lumbar vertebrae with 3D CT images. Problems with existing segmentation methods include the inability to completely segment, failure to process all the data, or an excessive need for hand labor. A new method was proposed to segment individual lumber vertebrae using CT images. The entire backbone is first segmented from CT images, and then each single centrum and intervertebral facet joints are disconnected, thereby segmenting out the lumbar vertebra of interest. Evaluation using real data and synthetic data indicate a successful highly automatic segmentation of single lumbar vertebrae. This method provides doctors with an important means of computer-aided diagnosis, as well as being useful in biomechanics and other fields of research.