The present invention relates to a composition for inducing differentiation of myeloid-derived suppressor cells (MDSC) and a method for inducing differentiation thereof, which comprises a macrophage-colony stimulating factor (M-CSF) and an interferon- the present invention provides a composition for inducing differentiation into a myeloid-derived suppressor cell (MDSC) comprising interferon-γ (IFN-γ) as an active ingredient. The present invention also relates to a bone marrow-derived inhibitory cell (B-cell) comprising a step of inducing differentiation into bone marrow-derived inhibitory cells (MDSC) by treating macrophage colony stimulating factor (M-CSF) and interferon- 0.0 >; (MDSC). <; / RTI >; In addition, the present invention provides a bone marrow-derived inhibitory cell (MDSC) differentiated by the differentiation induction method and a pharmaceutical composition for suppressing immune reaction comprising the same as an effective ingredient.본 발명은 골수유래억제세포 (myeloid-derived suppressor cell; MDSC) 분화 유도용 조성물 및 이의 분화 유도방법에 관한 것으로서, 대식세포 콜로니 자극 인자(Macrophage-colony stimulating factor; M-CSF) 및 인터페론-γ (interferon-γ; IFN-γ)를 유효성분으로 포함하는 골수유래억제세포 (myeloid-derived suppressor cell; MDSC)로의 분화 유도용 조성물을 제공한다. 또한, 본 발명은 골수세포에 대식세포 콜로니 자극 인자(M-CSF) 및 인터페론-γ (IFN-γ)을 처리하여 골수유래억제세포 (MDSC)로 분화를 유도하는 단계를 포함하는 골수유래억제세포 (MDSC)로의 분화 유도 방법을 제공한다. 또한, 본 발명은 상기의 분화 유도 방법에 의해 분화된 골수유래억제세포 (MDSC) 및 이를 유효성분으로 포함하는 면역반응 억제용 약학 조성물을 제공한다.