OBJECTIVE To explore the effect of silencing the Notch2 gene by small interfering (si)RNA on the proliferation of the HepG2 human hepatocellular carcinoma (HCC) cells. METHODS Notch2-siRNA was transfected as a liposomal formulation into HepG2 cells. The non-HCC cell lines SG07901 (gastric cancer) and SW620 (colon cancer) were used as controls. The mRNA expression of Notch2 and Hesl were detected by RTPCR, and the protein expression of Notch2 was detected by western blotting. The proliferation of transfected HepG2 cells was assessed by the cell counting kit-8 (CCK8) colorimetric assay. RESULTS The untransfected HepG2 cells showed significantly upregulated transcript expression of Notch2, and not of Notch1, Notch3 or Notch4, compared to the other non-HCC cell lines. Following transfection of Noteh2-siRNA into HepG2 cells, the mRNA expression of Notch2 and Hes1 and the protein expression of Notch2 were significantly decreased. The rales of proliferation inhibition in HepG2 following transfection of Notch2-siRNA showed an increasing time-related trend, with 2.64% ± 1620% at 12 h, 38.34% ± 8.80% at 24 h, 70.05% ± 7.80% at 48 h, 70.78% ± 10.00% at 72 h, and 74.22% ± 4.80% at 96 h.The inhibition rate at 24 h of transfection was significantly different from that of the groups of control cells. CONCLUSION Notch2 is upregulated in the common HCC cultured cell line HepG2. siRNA-mediated silencing of Notch2 exerts inhibition effects on HepG2 proliferation, suggesting the potential for this approach as targeted therapy for treating HCC.