Objective: To investigate the expression of CXCR4 on HL-60 cell line and the proliferation,apoptosis of HL-60 cell line cocultured with bone marrow stromal cells, so as to assess the possibility of 12G5, an anti-CXCR4 monoclonal antibody, in eradicating the minimal residual disease. Methods: The activity of SDF-1 was inhibited by 10 μg/ml 12G5. After treatment with 12G5, the status of adhesion was observed, and the adhesion rates, apoptosis and cell cycles were detected after 24 h of treatment. Cell growth rates were measured by trypan blue exclusion. Cell growth curve was plotted, and the expression of PCNA and apoptosis related protein including PCNA, Bcl-2 and Fas were detected with immunohistochemical technique. Results: (1) There was middling degree expression of CXCR4 on HL-60 membrane. From 0 h to 6 h, as the time of 12G5 incubation along, the expression of CXCR4 decreased gradually. (2)After treatment for 24 h, the adhesion rates in the experiment group and the control were (39.4±7.9)％and (51.4±5.9)％, respectively. (3)After treatment for 24 h, the percentage of HL-60 cells in G0/G1 phase were (55.21±4.9)％, and that in S phase and G2/M phase were (30.40±4.1)％ and (14.39±5.2)％, respectively, with the corresponding proportions being (44.67±2.2)％, (45.30±3.7)％, and (10.03±2.6)％ in the control. (4) The percentage of apoptotic HL-60 cells was (8.95±1.7)％ in the experiment group, compared to (3.97±2.4)％ in the control. (5)The survival rates of HL-60 cells decreased markedly at 48 h to 96 h, and the proliferation slowed down at this time duration. (6)The expression of PCNA and Bcl-2 down-regulated significantly, but the Fas protein expression was up-regulated. Conclusion: 12G5 could inhibit the capability of adhesion and proliferation of HL-60 cells and it can induce more cells to enter G0/G1 phase and promote apoptosis. It may be helpful by inhibiting the bioactivity of SDF-1 with 12G5 in the therapy of marrow residual disease.