ObjectiveUtilization of liquid smoke rice husk can be used as an alternative treatment because of the antimicrobial properties. Advances in drug delivery systems are increasingly developing to increase the bioavailability of drugs and reduce the side effects of these drugs, namely nanoparticles. In this study, nanoparticles of liquid smoke rice husk (nLSRH) were tested the antimicrobial againstPorphyromonas gingivalis.Materials and MethodThis type of research is an experimentalin vitrolaboratory usingPorphyromonas gingivalisculture. nLSRH contained liquid smoke rice husk concentration of 1, 2.5, 5, 7.5, 10, 12.5, 15, and 17.5%. The antibacterial was performed using the dilution methods.ResultsThe nLRSH concentration of 1% showed clearest medium. The highest number of coloniesPorphyromonas gingivaliswas observed at nLSRH concentration of 1% (40.3 colony-forming unit [CFU]) and decreased at a concentration of 2.5% (11.3 CFU); other concentration or no bacterial colony growth was found. The nLSRH concentration of 2.5% can be determined as the minimum inhibitory concentration and nLSRH concentration of 5% can be determined as the minimum bactericidal concentration.ConclusionnLSRH have antimicrobial activity againstPorphyromonas gingivalis. This finding able to drive the next research to develop nLSRH as gingival and periodontitis disease is caused byPorphyromonas gingivalis.