Mechanical enlargement of the root canals must be accompanied by copious irrigation of specific irrigants that can render the prepared canal as bacteria-free as possible. The use of herbal alternatives has become the dernier cri owing to the increase in antibiotic resistance against chemical medications. No study has been performed to check the antimicrobial activity of Nigella sativa oil against the persistent endodontic pathogen, E. faecalis & hence this preliminary study aims to compare the antibacterial potency of Nigella sativa oil against E. faecalis and compare it with 2.5% sodium hypochlorite. Nigella sativa oil and 2.5% Sodium Hypochlorite were tested against Enterococcus faecalis-ATCC 29212 to check for their Minimum Inhibitory Concentration (MIC) by double dilution method and Mean Kill Time as a measure of their antimicrobial potency to be used as an intracanal irrigant. The results show that Nigella sativa oil has a MIC of 0.4µl/ml while 2.5% sodium hypochlorite has a MIC of 50µl/ml against E. faecalis. Nigella sativa oil has bactericidal effects by 30mins of its exposure to E. faecalis while 2.5% sodium hypochlorite showed reduced growth of E. faecalis at the end of two-hour exposure. Under the limitations of this study, it was concluded that Nigella sativa seed oil has a better antimicrobial effect than 2.5% sodium hypochlorite against E. faecalis