The endothelium forms the main barrier to the passage of macromolecules and circulating cells from blood to tissues. Endothelial permeability is in large part regulated by intercellular junction. The article here dicusses the development of endothelial cell-to-cell junction. The types of endothelial junctions, transduction, regulation of changes of endothelial cell-to-cell junction, the effects of the flow in vasculature and the leukocytic extravasation have been discussed. It was emphasized that the changes of endothelial junctions and skeleton were important in regulating endothelial permeability, leukocyte extravasation and reorganization of vascular endothelial cell-to-cell junction.