Endodontic infections, the infection of the dental root canal system, have a polymicrobial nature that characterized by mostly anaerobic and some facultative bacteria. Among them, Enterococcus faecalis is associated wit h a significant number of persistent endodontic infecti ons. It has a large number of virulence factors tha t may be related with various stages of pathogenesis. Eradication of infectious agents or significantly reduction the m icrobial load is very important in treatment of endodontic infection s. Although current treatment options are combinati on antibiotic therapies, E. faecalis can also have acquired antib iotic resistance to numerous classes of antibiotics due to its high genome plasticity. Treatment failures and resistanc e development have made therapy difficult. In this paper, we discuss the physiological features and ability of b iofilm formation of E. faecalis, as well as pathoge nesis and effective treatment of endodontic infections by E. faecalis. Knowledge about the pathogenesis of E. fa ecalis endodontic infections and mechanisms of E. faecalis antimicrobial resistance may help to prevent failu res of endodontic treatment attributed to this organism.