Salivary glands are exocrine glands secreting saliva into the oral cavity. The primary function of the saliva is to protect and hydrate the mucosal structures of the oral cavity. The lubrication and hydration of the oral mucosa is provided by the water content of the saliva which forms approximately 99% of its composition. Aquaporins are water channels expressed in acini of salivary glands and play an important role in formation of saliva. Aquaporins are transmembrane water permeable proteins involved in transcellular water flow. In addition to being permeable to water, some Aquaporins can be permeable to small solutes, including cations, glycerol and gases. The present article reviews the basic histology of salivary gland, its ductal system and also physiology of secretion of saliva and highlights the role of Aquaporins in saliva formation.