Background and aims: Rising evidence points to endothelial-to-mesenchymal transition (EndMT) as a significant source of the mesenchymal cell population in fibrotic diseases. In this context, we hypothesized that liver endothelial cells undergo EndMT during fibrosis progression. Methods: Cirrhosis in mice was induced by CCl₄. A transgenic mouse expressing a red fluorescent protein reporter under the control of Tie2 promoter (Tie2-tdTomato) was used to trace the acquisition of EndMT. Sinusoidal vascular connectivity was evaluated by intravital microscopy and high resolution 3D confocal microscopy. Results: A modest but significant fraction of liver endothelial cells from both cirrhotic patients and CCl₄-treated Tie2-tdTomato mice acquired an EndMT phenotype characterized by the co-expression of CD31 and α-SMA, compared with non-cirrhotic livers. BMP-7 inhibited the acquisition of EndMT induced by TGF-β1 treatment in cultured MLiECs from control mice. EndMT was also reduced significantly in vivo in cirrhotic Tie2-tdTomato mice treated intraperitoneally with BMP-7 compared with untreated mice (1.9±0.2 vs. 3.8±0.3 %, respectively; p<0.05). The decrease of EndMT in cirrhotic livers correlated with a significant decrease in liver fibrosis (p<0.05) and an improvement in the vascular disorganization rate (p<0.05). Conclusions: We demonstrated the acquisition of the EndMT phenotype by a subpopulation of endothelial cells from cirrhotic livers in both animal models and patients. BMP-7 treatment decreases the occurrence of the EndMT phenotype and has a positive impact on the severity of disease by reducing fibrosis and sinusoidal vascular disorganization.