ObjectiveTo investigate regulation mechanism of glypican-3 (GPC3) on Hippo signaling pathway and its effects on biological behavior of hepatocellular carcinoma Huh7 cells. MethodsShort hairpin RNAs (shRNA) targeting GPC3 and Yes-associated protein 1 (YAP1) genes were constructed. All of the shRNAs were transfected into Huh7 cells by liposome transfection in order to screen out the stable expression cell lines. The expressions of GPC3 and YAP1 in Huh7 cells were detected by PCR and Western blot in order to screen out the effective shRNAs. The proliferation, invasion, and apoptosis of Huh7 cells were detected by Edu cell proliferation assay, transwell, and flow cytometry. GPC3 shRNA transfection experiments were divided into 6 groups:non-transfection group, empty vector group, GPC3-714-shRNA group, GPC3-647-shRNA group, GPC3-1718-shRNA group, and GPC3-2134-shRNA group. YAP1 shRNA transfection experiments were divided into 6 groups:non-transfection group, empty vector group, YAP1-906-shRNA group, YAP1-1363-shRNA group, YAP1-1666-shRNA group, and YAP1-2895-shRNA group. GPC3 regulation experiments were divided into 5 groups:non-transfection group, empty vector group, GPC3-1718-shRNA group, GPC3-1718-shRNA+ rhYAP1 group, and YAP1-1666-shRNA group. Results① GPC3-1718-shRNA and YAP1-1666-shRNA plasmids were successfully constructed to silence the expressions of GPC3 and YAP1. ② The expressions of GPC3 mRNA and protein in each transfection group were significantly lower than those in the non-transfection group (P<0.05) and the empty vector group (P<0.05), while which in the GPC3-1718-shRNA group was significantly lower than those in all the other transfection groups (P<0.05). The expressions of YAP1 mRNA and protein in each transfection group were significantly lower than those in the non-transfection group and empty vector group (P<0.05), while which in the YAP1-1666-shRNA group was significantly lower than those in all the other transfection groups (P<0.05). ③ The expressions of YAP1 mRNA and protein in the GPC3-1718-shRNA group and the YAP1-1666-shRNA group were significantly lower than those in the non-transfection group (P<0.05) and the empty vector group (P<0.05), while which in the GPC3-1718-shRNA+rhYAP1 group were significantly higher than those in the GPC3-1718-shRNA group (P<0.05) and the YAP1-1666-shRNA group (P<0.05). ④ Compared with the non-transfection group and the empty vector group, the abilities of cell proliferation and invasion in the GPC3-1718-shRNA group and the YAP1-1666-shRNA group were significantly decreased, and the cell apoptosis was significantly increased (P<0.05); The cell proliferation, invasion, and apoptosis in the GPC3-1718-shRNA+rhYAP1 group were significantly improved (P<0.05). ConclusionGPC3 is likely to affect biological behavior of hepatocellular carcinoma Huh7 cells through regulation of YAP1 in Hippo signaling pathway.