Sleeping with back pain but not after getting up can be caused by the following reasons: First, tumors or metastases in the lumbar spine can appear as resting pain when sleeping, which is a characteristic of tumor pain, and early lumbar spine MRI, CT and blood tests should be taken for early diagnosis and treatment. Second, osteoporosis of the lumbar spine. Severe osteoporosis of the lumbar spine can lead to back pain when sleeping, and the pain can be relieved after getting up, especially when there is a compression fracture of the lumbar spine, so early X-ray and CT of the lumbar spine should be taken, and if necessary, consultation should be made to the endocrinology department for early treatment. Third, severe lumbar dorsal myofasciitis can also occur when sleeping with low back pain, and early examination should be done to exclude other diseases for diagnosis.