The common reasons for back pain at night when sleeping and not during the day are the following: 1, the bed is too soft or too hard when sleeping at night, the lack of effective support for the waist, so that the lumbar force is not balanced, resulting in strain and injury outside the waist, resulting in symptoms of back pain. The daytime is dominated by the standing and sitting position, there is no such reason, so the pain may not appear during the day. 2, during sleep the body is relatively quiet, blood pressure drops, and the overall blood circulation is very slow. When there is local inflammation, it is not conducive to the dissipation and dilution of inflammation, which leads to the accumulation of local metabolic products and inflammatory stimulation, it will be easy to have pain during sleep. 3, for the human body to feel, pain is more obvious at night, especially at night when the pain is more serious, which is determined by the characteristics of nerve sensation, mainly because the brain’s control of the lower center is reduced, during sleep The lower for center is relatively excited, so the pain sensation is also relatively excited. During the daytime, patients usually move around, the local blood circulation is very good, which is conducive to the dilution of inflammation, and the pain may not be obvious. The main causes include the above, and patients are advised to go to the hospital for consultation and clear diagnosis.