The human gravity line (GL) is a virtual vertical line that passes through the centre of gravity (COG) of the human body and holds significant importance in assessing human biomechanics. Due to the inability to directly determine GL through imaging methods, its application in past research and clinical practice has been somewhat limited. However, with the advancement of technology, the measurement and application of GL have made remarkable progress, becoming an essential supplement to traditional radiographic measurements and demonstrating an increasingly broad application prospect in the field of spinal health. This review summarizes the GL anatomical basis, measurement methods, and its relationship with other commonly used vertical lines. Furthermore, the current status of GL’s clinical application in the field of spinal health is also summmrzied, and its potential role in the diagnosis and treatment of spinal diseases is discussed. It is hoped that the findings will offer new perspectives for the diagnosis and treatment of spinal diseases, and promote further research and application of GL in the field of spinal medicine.