Objective To identify the characteristics of the subtype of PMA-induced THP-1 macrophages by flow cytometry analysis. Methods THP-1 monocytic cells differentiate into macrophages promoted by PMA, then induced into M1 and M2 by adding different cytokines, such as LPS,IL-6 and IFN-γ for THP-1-M1, IL-4,IL-13 and IL-6 for THP-1-M2. Morphology of cells were observed under a microscope and the expression of CD14, CD68, CD16, CD80, CD86, CD163, CD206, CD209, CD83, CD1a, CD11c, HLA-DR were detected by flow cytometry. Results The macrophages stimulated by PMA became adherent; THP-1-M1 and THP-1-M2 lost their spherical morphology, appeared more irregular with many obvious projections. The expression of CD83, CD1a, CD11c, HLA-DR which had the function of antigen presenting on the surface of THP-1-Mφ were very low, and most of them were negative, but those of THP-1-M1 and THP-1-M2 were very high. Conclusions The macrophages differentiated from THP-1 stimulated by PMA are weak in antigen presenting function.