Aim: To determine bacterial count and inhibition zone following photoactivated oral disinfection versus sodium hypochlorite solution on root canal bacteria. Methodology: This Invitro study was conducted at Pediatric Dentistry and Dental Public Health Department, Faculty of Dentistry, Cairo University and Medical Microbiology and Immunology Department, Faculty of Medicine, Cairo University. Bacterial count and zone of inhibition were performed on Enterococcus faecalis and Streptococcus intermedius. A total number of 36 samples were divided on three main groups. First group was photoactivated oral disinfection, second group was photoactivated oral disinfection with sodium hypochlorite ad finally control group was sodium hypochlorite. All these groups were tested for both bacterial count and inhibition zone. Results: Regarding Enterococcus faecalis and Streptococcus intermedius count, the highest value was in photoactivated oral disinfection, followed by photoactivated oral disinfection with sodium hypochlorite, whereas the lowest value was in sodium hypochlorite in 24 and 48 hours. Regarding Enterococcus faecalis and Streptococcus intermedius inhibition zones, the highest value was in sodium hypochlorite, followed by photoactivated oral disinfection with sodium hypochlorite, while the lowest value was in photoactivated oral disinfection in 24 hours. Conclusions: Sodium hypochlorite may be the best available irrigant owing to its wide antibacterial spectrum followed by photoactivated oral disinfection with sodium hypochlorite, whereas the least effective was photoactivated oral disinfection.