Myasthenia gravis is an autoimmune disease caused by dysfunction of transmission at the nerve-muscle junction. The main clinical manifestations are partial or generalized skeletal muscle weakness and easy fatigue, with symptoms worsening after activity and decreasing after rest. It is widely believed that its development is related to infections, drugs and environmental factors. There is no specific medication to cure the disease, and long-term medication is required to maintain the stability of the disease. Hyperbaric oxygen combined with acupuncture (i.e., after acupuncture immediately into the chamber for hyperbaric oxygen therapy) and drug therapy has good effect on myasthenia gravis. It is rare to see a patient with significant effect after one treatment, which is reported as follows: The patient is a 57-year-old male. Ten years ago, he had symptoms of weakness in the limbs, and was clearly diagnosed with myasthenia gravis, and his condition was basically stable with long-term medication. On September 21 of this year, the patient suddenly developed bilateral eyelid ptosis. He was treated with hormones and other drugs in an outside hospital, but the effect was not good, so he came to our department. At the time of the visit, the patient was unable to open both eyelids and needed to use his hands to hold them open when communicating with others. After considering the patient’s condition, he was treated with hyperbaric oxygen and acupuncture. After one treatment, both eyes could be opened, more significantly in the left eye, and after three treatments, the patient’s right eyelid drooping symptoms improved significantly. After 5 treatments, the patient’s right eyelid was basically back to normal.