ObjectiveTo analyze the surgical efficacy and influencing factors of myasthenia gravis (MG) patients with thymic atrophy after thymectomy. MethodsThe clinical data of MG patients with thymic atrophy undergoing thymectomy between October 2014 and May 2018 in Daping Hospital of Army Medical University and Shijiazhuang People Hospital were retrospectively analyzed. ResultsA total of 71 patients were collected, including 40 males and 31 females with a mean age of 45.17±12.42 years. All patients received the surgery successfully. After the surgery, 20 (28.17%) patients were stable remission, 12 (16.90%) patients were minimal manifestation status,19 (26.76%) patients were improved, 5 (7.04%) patients showed no change, 3 (4.23%) patients were worsened, 10 (14.08%) patients were exacerbated and 2 (2.82%) patients were dead. Multivariate logistic regression analysis showed that the preoperative illness duration (OR=4.61, 95%CI 1.13-18.85, P=0.03), and postoperative pyridostigmine combined with immunosuppressive (OR=0.12, 95%CI 0.03-0.45, P=0.00) were independent risk factors for long-term efficacy of thymectomy for MG patients with thymic atrophy. ConclusionEarly surgery after diagnosis of MG and postoperative pyridostigmine combined with immunosuppressive treatment is beneficial to the prognosis of MG patients with thymic atrophy.