The clinical symptoms of non transfusion dependent non severe aplastic anemia (NSAA) are often lighter than that of severe aplastic anemia. Clinical observation is often used and the treatment should be given according to the follow-up results of peripheral blood routine and the survival condition of the patients. In recent years, a number of studies at home or abroad have tended to intervene earlier. The risk of observation and waiting for disease progression is higher. Early immunosuppression should be considered. For the treatment of non transfusion dependent non severe aplastic anemia, the commonly used treatment regimen is androgen combined with CSA. But the investigators find that Levamisole hydrochloride (LMS) as a commonly used immunomodulatory drugs may be helpful to improving immune disorder symptoms in NSAA patients. Therefore,the investigators are conducting a prospective, randomized controlled study to compare the rate, side effects and long-term survival in non transfusion dependent patients with NSAA between the androgen+CSA group and the androgen+CSA+LMS group.