Dental caries is a multifactorial microbial disease of the tooth and is one of the most common health problems. Saliva, a complex mixture of fluids is secreted by the major and minor salivary glands that surrounds the hard and soft tissues of the oral cavity that is composed of organic and inorganic components. Saliva is one of the intraoral host factors that influence caries development. Salivary components, its flow, viscosity, buffering capacity, etc., play a major role in the prevention, initiation and progression of the disease. As a diagnostic fluid, saliva offers distinctive advantages over serum because it can be collected non-invasively by individuals, even by patient. In future, there can be an increased utilization of saliva as a diagnostic fluid.