<p>Neighborhood environments play a critical role in shaping youth development. Although prior research has focused on individual and family-level factors, there remains a gap in understanding neighborhood-level protective mechanisms for adolescents exposed to child maltreatment. This study examined two forms of Neighborhood Informal Social Control of Child Maltreatment (ISC_CM) -- protective and punitive ISC_CM -- as potential moderators of the relationship between child maltreatment and adolescent depression, aggressive behavior, and suicidal risk among middle and high school students in South Korea utilizing a cross-sectional survey design. Structural equation modeling results indicated that punitive ISC_CM, such as taking firm action to address punitive parenting, marginally moderated the association between child maltreatment and aggressive behavior, but not depression or suicidal risk. Protective ISC_CM, defined as offering supportive resources in instances of harmful parenting, demonstrated a main effect on all outcomes, but no significant moderation effect was observed. These findings suggest that protective neighborhood interventions are generally beneficial for youth mental health, even if they do not specifically buffer the effects of maltreatment. Community-based programs addressing adolescent mental and emotional health may benefit from encouraging neighbors to establish shared social norms regarding child maltreatment and to intervene in cases of paternal maltreating behaviors. Major keywords. Neighborhood protective factors, collective efficacy, informal social control, suicidal risk, child maltreatment, ISC_CM.</p>