The effect of hydrogen peroxide, an antiseptic dental treatment, onAggregatibacter actinomycetemcomitans, the main causative agent of localized invasive periodontitis, was investigated. Hydrogen peroxide treatment (0.06%, 4× minimum inhibitory concentration) resulted in the persistence and survival of approximately 0.5% of the bacterial population. The surviving bacteria did not genetically acquire hydrogen peroxide resistance but exhibited a known persister behavior. Sterilization with mitomycin C significantly reduced the number ofA. actinomycetemcomitanspersister survivors. RNA sequencing of hydrogen peroxide-treatedA. actinomycetemcomitansshowed elevated expression of Lsr family members, suggesting a strong involvement of autoinducer uptake. In this study, we found a risk ofA. actinomycetemcomitanspersister residual from hydrogen peroxide treatment and hypothesized associated genetic mechanisms of persister from RNA sequencing.