Infrared thermography is a comprehensive science and technology of acquiring and analyzing thermal information by combining medical, physical and computer science multidisciplinary. It uses infrared remote sensing to sense the infrared heat radiation signal of human body and reflects the change of human body surface temperature and its distribution characteristics with pseudo-color sensitively, digitizes the change pattern of limb temperature difference, and provides objective data for clinical diagnosis and efficacy observation of lumbar intervertebral disc herniation. It was found that patients with lumbar disc herniation had obvious high-temperature areas in the lumbosacral region in the shape of a pike, diamond, lamellar uniform red or deep red. The temperature of the affected lower extremity was significantly lower than that of the healthy extremity and was light blue or blue, consistent with the area of spinal innervation on the side of the herniation. When a lumbar intervertebral disc is herniated, stimulation of the herniated material triggers aseptic inflammation of the nerve roots and their surrounding tissues, with increased and infiltrated local histamine and other pain-causing substances, and microvascular dilation occurs, leading to increased blood flow, which exhibits increased temperature in the skin area of the corresponding segment near the lumbar spinal midline. On the other hand, the sinus vertebral nerve stimulates the sympathetic nerve accompanying the spinal nerve, causing vasoconstriction and slowing of blood flow in the area innervated by the spinal nerve, which results in infrared thermography showing a decrease in temperature. Infrared thermography, as functional imaging, plays a great complementary role to structural imaging and is able to show the functional status of the body through visualized images and objective data, which is a perfect and complementary to the diagnosis of lumbar disc herniation. Its objective response to the internal pathological changes of the organism through the external manifestations.