Dental disease is one of the most prevalent public health concerns. The problems caused by dental caries affect all age groups, and treatment is both expensive and labor-intensive.1 Dental caries and periodontal diseases are infectious diseases caused by common oral bacteria; therefore, controlling or even reducing the levels of these causative pathogens, such as S. mutans and E. faecalis, is a key step in the prevention and treatment of these diseases. 2 Dental caries is a common oral disease caused by many cariogenic microbes, including Lactobacillus spp., Streptococcus spp., and Actinomyces spp., which usually form plaque biofilms on the tooth surfaces. 1 Dental plaque is initially synthesized by the GTase from S. mutans, and oral microorganisms then colonize and accumulate in this water-insoluble glucan layer. The viridans streptococci S. salivarius, S. sanguis, and S. mutans were the most representative human cariogenic bacteria included in the present study; however, these species are also moderately resistant to antibiotics. Actinomyces spp. are involved in early plaque development on tooth surfaces and contribute to root caries and periodontal infections. 5E. faecalis is an opportunistic pathogen that is frequently isolated from asymptomatic and persistent endodontic infections, especially from the failed root canals undergoing retreatment. 15E. faecalis is a better survivor than other root canal microbes, being able to resist various harsh conditions such as bile salts and starvation as well as many antibacterial agents. 16 The characteristics of these oral bacteria determine the antimicrobial agents that can be used for the prevention and treatment of dental diseases. In our study, aqueous extracts of 14 medicinal herbs were prepared and evaluated for their antimicrobial activities against five species of oral bacteria.