Night back pain, stomach pain during the day without pain may consider the existence of lumbar muscle strain, fasciitis, ankylosing spondylitis, pelvic inflammatory disease and other conditions. 1. Lumbar muscle strain, fasciitis: due to sedentary, overwork, improper posture, etc., may lead to muscle strain of the low back, as well as cold, etc. caused by myofasciitis, in the resting state of the night may be due to a further decline in blood circulation, etc., leading to pain, daytime activities will increase blood circulation, resulting in pain is not obvious. 2. Ankylosing spondylitis: If ankylosing spondylitis is caused by heredity, immunity and other factors, it will also show typical nighttime low back pain, and some people may have stomach pain. 3. Pelvic inflammatory disease: for women, if there is pelvic inflammatory disease and other gynecological inflammatory diseases, may also appear at night back, abdominal pain performance. There are other causes of back pain at night, stomach pain during the day without pain, such as urological diseases, etc., it is recommended to go to the hospital in a timely manner to improve the relevant examinations, clear diagnosis and then comply with the doctor’s instructions for targeted treatment to avoid delays in the condition.