Objective:To investigate the effect on invasion and metastasis of HCCLM3 cells blocked peroxisome proliferators-activated receptor gamma(PPARγ) expression by RNA interference method. Methods:Transwell chambers were used to construct tumor cell invasive models,PPARγ shRNA(pshPPARγ group) and plasmid pBi-hU6-DNA(pshPPARγ-N group) were transfected into HCCLM3 cells. Untreated HCCLM3 cells were regarded as negative control(control group). The changes of PPARγ expression in three groups were detected by semi-quantitive RT-PCR and Western blot analysis. Cell adhesion,migration,invasion and locomotion of cells were observed,Meanwhile,MMP2,TIMP2 and integrin β1 mRNA expression were detected by RT-PCR. Results:PPARγ expression in pshPPARγ group was 80.5% lower than the other two groups at mRNA level. In pshPPARγ groups,the number of cells crawled over semipermeable membrane of Tanswell chambers were 68 ± 7,the number of cells permeated through ECM were 17 ± 3,and the ability of cell adhesion decreased significantly. After 2 h,adhesion cell counts in pshPPARγ groups are 49 ± 9,the time when cells healed the wound were(6.40 ± 1.14)d. There were significant differences between pshPPARγ group and the other two groups(P < 0.01). In pshPPARγ group,MMP2 and integrin β1 mRNA of HCCLM3 cells decreased significantly,but TIMP2 increased. Conclusion:Knockdown PPARγ expression with RNA interference technology can significantly inhibit the invasion and metastasis of HCCLM3 cells, which might be the result of the decrease expression of integrin β1 to balance MMP2/TIMP2.