Objective To establish a nude mice model for NB4/ShHMGA2 xenograft and explore the effect of HMGA2 knockdown on hematological malignancies. Methods NB4/ShHMGA2 or NB4/ShControl cell lines were established by transfecting the recombinant Lentivirus-HMGA2shRNA and the vacant Lentivirus-NC-marked into NB4 cells. The knockdown of HMGA2 was identified by RT-PCR and Western blot. Ten male BALB/c nude mice aged 4 ~ 5 weeks were equally divided into two groups. The mice irradiated by 4 Gy 60 Co were subcutaneously injected with 8 × 106 NB4/ShHMGA2 or NB4/ShControl cells into one side of axilla. The volumes of xenograft tumor were evaluated using the equation volume (mm3) = (L × W2)/2. The xenograft tumor section was detected by IHC with Ki-67 antibody. Results NB4 cell xenograft tumors developed in all mice of both the two groups. The NB4/ShHMGA2 cells in the nude mice grew at a lower rate than those in the controls. There were statistically significant differences in the volume and weight of xenograft tumor between the two groups [(1 484.25 ± 156.342)mm3 vs (3 228.674 ± 285.64)mm3, P < 0.05] and [(2 135.33 ± 198.05) mg vs (650.46 ± 85.12)mg, P < 0.05]. The Ki-67 protein level in NB4/ShHMGA2 cells xenografts was lower than that in the controls. Conclusion The knockdown of HMGA2 could inhibit proliferation of NB4 cells in NB4 cells xenograft tumor.