This study was aimed to investigate the effects of the introplasmic interferon-γ level in circulating T cell of patients with aplastic anemia (AA) and its clinical significance. The interferon-γ level before and after immuno-suppressive therapy was monitored by flow cytometry. The results indicated that the higher interferon-γ level was detected in 28 out of 50 AA patients, detected rate was 56%. The effective rate of immunosuppressive therapy for AA patients with higher interferon-γ level was up to 85.7% (24/28). The decrease of interferon-γ level in these patients positively correlated with hemogram recovery to normal level and obviously earlier than hematologic remission. It is concluded that the immunosuppressive therapy shows better efficacy for AA patients with high interferon-γ level, moreover the change of interferon-γ level is earlier than hematologic change, that is important for predicting the therapeutic efficacy and relapse of disease.