This study aims to investigate the effect of substances secreted or metabolized by vascular endothelial cells on epithelial-mesenchymal transition (EMT) of hepatocellular carcinoma cells under indirect co-culture condition. Human hepatocellular carcinoma cell line QGY-7703 was cultured in vitro, and then was co-cultured with conditioned medium of human umbilical vein endothelial cells (HUVEC). The morphological changes of QGY-7703 cells were observed by inverted phase contrast microscopy. The migration ability of QGY-7703 cells was analyzed by scratch-wound assays. The effect of conditioned medium on the expression and distribution of EMT related proteins was detected by Western blot and immunofluorescence assays, respectively. The results showed that the QGY-7703 cells gradually changed from polygonal to spindle shape, the migration ability promoted significantly, and both the expression and distribution of EMT related marker changed in a time-dependent manner after co-culturing. The results confirm that vascular endothelial cells can induce EMT in hepatocellular carcinoma cells under indirect co-culture condition.