Introduction: Chemo-mechanical preparation of the root canal system to reach an almost sterile condition, is the key for better endodontic results. Thus, root canal disinfection should be aiming to use effective irrigant activation techniques that will improve root canal disinfection in addition to an efficient irrigant . Methodology: Thirty three Single-rooted extracted permanent human teeth with mature apices were instrumented to tooth length to a K- file #25 in reaming action, using water as irrigant. Teeth were divided to 3 groups, each group in a silicone mold and sterilized. Teeth were then contaminated with E.feacalis. After incubation root canal instrumentation and irrigant activation was done according to groups. Group A: Xp endo finisher, Group B: Passive ultrasonic irrigation, Group C: conventional needle irrigation. Results: group A and B showed significantly greater bacterial reduction compared to group C. Conclusion: irrigant activation with XPF and PUI caused greater bacterial reduction than conventional needle irrigation.