Objective To observe the morphological features of the thoracolumbar intervertebral foramen and to provide anatomical data for clinic practive.Methods The height, length and sagittal width of the thoracolumbar intervertebral foramen from T 1 to L 5 were measured in 24 adult male skeletons.Results The sagittal width increased gradually from T 1 to T 4 and from T 9 to T 12, decreased gradually from L 1 to L 5;The height of intervertebral foramen gradually increased from T 1 to L 4, and were significantly greater than the corresponding sagittal width from T 1 to L 5 (P0.01);The length of intervertebral foramen decreased significantly from T 1 to T 4 and increased gradually from T 9 to L 5; the spinal nerve roots were located in the superior part of the intervertebral foramen and the space between them were larger in vertical orientation, smaller in sagittal orientation.Conclusion The spinal nerve roots lesions due to the stenosis of intervertebral foramen occur more frequently in the thoracic region than in the lumbar region and are usually found in sagittal direction.