Right lung cancer left shoulder and back pain may be caused by physiological reasons, right lung cancer left shoulder blade metastasis and other reasons. 1. Physiological reasons: muscle strain of left shoulder and back or lying on the left side all the time during sleep may lead to left shoulder and back pain, rest, local hot compress and change of sleeping position can relieve the symptoms of shoulder and back pain. 2. Right lung cancer metastasis to left shoulder blade: right lung cancer can be metastasized to left shoulder blade through blood circulation, and the tumor infringes on left shoulder blade, leading to the destruction of bone quality of left shoulder blade and triggering pain. Right lung cancer left shoulder and back pain should go to the hospital in time, improve the examination and give targeted treatment after clarifying the cause of the disease.