There are several possible reasons for waking up with arm and shoulder pain: first, wind and cold, if you accidentally get blown into the wind or have cold triggering causes while sleeping, you can wake up with arm and shoulder pain; second, myofasciitis, patients with myofasciitis can have pain on the inside of the scapula as the first symptom, which can radiate to the ipsilateral shoulder and upper limb, with symptoms of soreness and weakness. Third, cervical spondylosis, when cervical spondylosis compresses the nerve roots, the symptoms of pain and numbness in one arm and shoulder can appear, especially at night when sleeping in an incorrect posture can lead to increased pressure on the nerve roots, and the symptoms of pain in the arm and shoulder when waking up, then early cervical spine X-ray, CT, MRI should be performed. X-rays, CT, and MRI examinations should be performed at an early stage for early diagnosis and treatment.