Cariogenic bacteria producing or promoting the development of tooth decay leads to the breakdown of teeth. Cavities become more common in both children and adults in recent years. Anti cariogenic properties of 5 crude extracts from different plants species were tested against Streptococcus mutans. The determination of the antibacterial activity by agar well diffusion method showed that 5 plant extracts tested exhibited antibacterial activity against Streptococcus mutans. Phytochemical screening of selected plants showed the presence of Saponin, Proteins, Tannins, Flavanoids, Steroids and reducing sugars. The above observations confirmed that some of these plant extracts possess bactericidal compounds, which inhibit the growth of Streptococcal dental caries.