Arm pain at night is mostly due to the following reasons: first, due to daily life arm long time strain, or do some strenuous exercise, lactic acid accumulation caused by muscle soreness, may also be due to the muscle repeatedly do the same action, strain, thus inducing pain. Secondly, due to the incorrect posture when sleeping at night, the arm is compressed for a long time, resulting in local soft tissue ischemia and poor blood flow, which induces pain, or it may be the arm is cold, chronic inflammation, which leads to pain. Third, frozen shoulder, cervical spondylosis leading to radiating pain in the arm, for some middle-aged and elderly patients, due to chronic inflammation of the shoulder joint leading to rotator cuff injury, resulting in arm soreness and swelling, and even shoulder joint activity is limited. Treatment should first lift the trigger to lift the muscle strain, followed by the application of anti-inflammatory and analgesic drugs to alleviate the symptoms, if the symptoms are more serious can also be assisted by some physical therapy, such as baking electricity, heat therapy, massage, can relieve muscle spasm, but also to control the pain caused by inflammation.