Due to the increasing resistance of microorganisms against antibiotics, the use of natural bioactive substances for the prevention of pathogenic bacteria is considered in food products . In this study, thymol, cardamom essential oil, L. plantarum cell-free supernatant (ATCC 14917), and their nanoparticle candies prepared and inhibition activities against S. mutans (ATCC 25175), which is important in causing tooth decay, was investigated . Moisture content, pH, and sensory analyzes of candies measured . Also, SEM and FTIR of treated candy samples were performed . All examined bioactive substances and their nanoparticles showed an inhibitory effect against S. mutans with different minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The prepared candies had pH 5.5 represented a bactericidal effect against S. mutans . SEM and FTIR results approved the antibacterial effects of prepared candies . According to the results, all of the prepared candies significantly decreased S. mutans in saliva compared to the control candy and they are suitable agents for S. mutans growth-inhibiting . Also, cardamom essential oil candy showed the most general acceptance in a sensory analysis by panelists.