Round cardamom extract (Amomum compactum) contains active agents such as tannin, flavonoid, saponin, triptenoid, and alkaloid. These substances are able to inhibit and destroy the bacteria, including Enterococcus faecalis. Enterococcus faecalis is proven can be survived in root canal as a single organism and resistance towards antimicrobial substances which used in root canal treatment. The mechanism of inhibitory activity of substances in round cardamom is by interupting the porin (transmembran protein) in outer membrane structure of a bacteria. Therefore, it can form strong polymeric chain which leads to damage of porin. The damage of porin which plays role as a gate in bacteria will decrease the ability of permeability in bacteria cell wall. The decreasing ability of permeability somehow will affect the nutrition intake of bacteria which leads to death of bacteria or inhibition of bacteria growth. The aim of the study was to know the effectivity of antibacterial activity of different round cardamom concetrations towards Enterococcus faecalis bacteria as root canal medicament.he design of the study was experimental laboratory using Enterococcus faecalis bacteria. The concentrations of round cardamom (Amomum compactum) were 25%, 50%, and 75% while aquades as a negative control and calcium hydroxide as a positive control. Antibacterial activity test was using well difussion disc during 24-48 hours in room temperature. Kruskall Wallis and Mann-Whitney test were used to determine the effectivity of antibacterial activity round cardamom (Amomum compactum). The inhibitory zones were formed in all concentration. The inhibitory zones for 25%, 50% and 70% were 2,06 mm; 3,36 mm; 4,28 mm respectively. The average of inhibitory zone in positive control was 5,08 mm.This research showed that all concentration of round cardamom extract influences as antibacterial activity of Enterococcus faecalis with significant result p= 0,000 (p<0,05).