V-ATPases are present in large numbers of organelles including lysosomes, endosomes, golgi complex and several secretory granules in animal cell. The function of V-ATPase is to generate protonmotive force and to cause limited acidification of the internal space of vacuolar system and extracellular compartments at the expense of ATP. The acidification and the electrochemical H^＋ gradient formed by V-ATPase serve an improtant function in endocytosis , exocvtosis, membrane traffic and transport systems of cells. In the families of H^＋-ATPases, increasing attention is being given to V-ATPase, about which much has been learned in recent years.