Background: The potential of the whole blood IFN-γ release assay (IGRA) as a surrogate for treatment response has been evaluated, but seems still challenging. To overcome this limitation, flow cytometry with intracellular cytokine staining has been investigated recently. The aim of our study was to longitudinally evaluate the change of Mycobacterium tuberculosis antigen (MTB Ag)-specific cytokine-secreting CD4+T cell subsets according to treatment. Methods: QuantiFERON-TB Gold In-Tube (QFT-IT) test and flow cytometry were performed before and after treatment in 28 patients with active TB. Results: 1) The frequencies of MTB Ag-specific IFN-γ+TNF-α+CD4+T cells and IFN-γ-TNF-α+CD4+T cells increased during active TB and then decreased significantly after treatment (p＜0.001). 2) The freqeuncy of MTB Ag-specific IFN-γ+TNF-α-CD4+T cell subset did not significantly change after treatment; rather, the proportion of IFN-γ+TNF-α-CD4+T cell subset increased sig-nificantly in treated TB patients (p=0.049). 3) In 8 patients with no decrease of IFN-γ concentration in QFT-IT test after treatment, the proportion of MTB Ag-specific TNF-α producing CD4+T cells decreased significantly, while the proportion of IFN-γ producing CD4+T cells increased significantly (p=0.017). Conclusion: Dynamic change of cytokine producing CD4+T cell subsets occurs after treatment, although there was no significant change of mean IFN-γ concentration in follow-up QFT-IT test. This may indicate that flow cytometric approach can be a new biomarker for monitoring the curative response of TB.