The most common prevalent diseases which affect the oral health are dental caries and periodontal diseases. Inspite of countless number of preventing measures these disease are still a major threat to dentistry. Hence the prevention of dental caries and periodontal diseases is mandatory for obtaining good oral health. Although fluoride and other preventive efforts have led to a dramatic decline in the dental caries, the ability to control the actual infection has been limited. The concept of microbial ecological change as a mechanism of preventing dental diseases in an important era in the dentistry. Regarding elimination of pathogenic members of oral cavity a new method such as probiotics approach has been emerged into the field. The current literature aims to review probiotics and its effect on oral health while emphasizing on safety concerns.