Background: Enterooccus faecalis is one of the bacteria that has been isolated from endodontic refactory like canal infection. E. faecalis is gram positive bacteria, non-motile, round shape bacteria. Ant-plant (Myrmecodia pendens Merr., & Perry) are plant that grow epifitly and hang or adhere to the aften plants in the stem hollow shoped that finally draw the attention of variorus ats to from colony. Ant-plant (M. pendens) contains flavonoid, saponin and tanin compounds. Research objective: the effects of antibacterial power of ethanol extract mouthwash from ant-plant (M. pendens) to E. faecalis. Research methodology: using purely laboratory experiment. Cultured Lactobacillus acidophilus was incubated with ethanol extract mouthwash from (M. pendens) with concentration of 10%, 25%, 50%, 75%, dan 100% for 18-24 hours within the temperature of 37°C with 4 controls that are positive control was using of Chlorhexidine gluconate 0.2%, negative control was the basic formula of mouthwash (0% concentrate), control bacteria, and control media. The antibacterial power test was using liquid dilution method to determine the MIC and solid dilution to determine the MBC. The data were analyzed using descriptive quantitative method. Research Results: ethanol extract of mouthwash from ant-plant (Myrmecodia pendens Merr. & Perry) has MIC at a formulation of II and MBC at a formulation of II. Conclusion: Ethanol extract mouthwash from ant-plant (Myrmecodia pendens Merr. & Perry) has antibacterial power to Enterococcus faecalis.