If you wake up with arm pain in the middle of the night, the causes are as follows: First, when sleeping, you like to sleep on your side, resulting in one arm pressed under your body, which will affect the blood circulation in the upper limbs, thus causing significant pain in the arm, resulting in waking up with pain. Second, when cervical spondylosis patients sleep, if the sleeping posture is incorrect and the sleeping pillow is too high, it will easily lead to pressure on the nerve roots in the cervical spinal canal, causing significant pain in the arm and waking up with pain. Third, not paying attention to the warmth of the arm when sleeping, resulting in a cold arm, thus triggering arm muscle, fascia, ligament spasm, will also cause arm pain wake up in the middle of the night. Therefore, after waking up with arm pain in the middle of the night, it is important to consult a doctor to see what the cause is and treat the cause to promote recovery from arm pain. After waking up with arm pain in the middle of the night, it is important to pay attention to the sleeping position, avoid sleeping on a pillow that is too high, and pay attention to keeping the arm area warm to avoid the onset of symptoms that can affect the patient’s sleep.