Left back pain in the morning can be caused by several reasons: first, heart disease, when the heart has a heart attack or angina pectoris, there can be left back pain in the morning, which can be accompanied by discomfort in the precordial area, then it is necessary to check the heart ultrasound, imaging and blood tests for diagnosis and early treatment. Second, dorsal myofasciitis, patients with dorsal myofasciitis can have pain in the back when waking up in the morning, and the pain is more obvious when getting cold or exerting oneself, so it is necessary to check and examine early to exclude other diseases for diagnosis. Third, cold, when the back is cold, there can also be acute inflammation of the fascia on one side of the back, resulting in pain in the back, then it is necessary to check and examine the body to exclude other diseases to diagnose. Fourth, intercostal neuralgia, patients with intercostal neuralgia can also have pain in the back at the intercostal nerve after waking up in the morning, which should be examined and treated with nerve nutrition and closure therapy early.