A comprehensive knowledge of spinal biomechanics is of importance for the understanding of all aspect of spinal kinematics, clinical analysis and management of spinal problems. The spine is a biomechanical structure. The spine is a composit of the motion segments including sophisticated ligaments and reinforced muscles on the back, abdomen and rib cage. With an integrity of the biomechanical structure of spine, it has fundamental biomechanical functions such as allowing the physiologic motion smoothly between the head & pelvis, resist the destructive motions by stiffening the spine, transfer the weight evenly and protect the delicate vulnerable spinal cord. The data of the biomechanical aspects enable to know the characteristics of spine, to analysis the clinical situations, and to manage the spinal problems in ideal manner so as to contribute spine in healthy.