Latino children are more than twice as likely to live in poverty than their non-Latino, White peers (Kids Count Data Center, 2017), yet limited work has aimed to understand neighborhood influences on pathways of mental health among Latino children. Substantial work documents the deleterious effects of living in a disadvantaged neighborhood on mental health outcomes throughout the lifespan (Leventhal & Brooks-Gunn, 2000). Parental and familial variables may explain neighborhood influences on children’s mental health during the first few years of life (May, Azar, & Matthews, 2018). The current study evaluated the influence of three neighborhood indicators (concentrated disadvantage, residential instability, and the percentage of residents identifying as Hispanic/Latino) on maternal postpartum depressive symptoms and child behavior problems at 3 and 4.5 years via mediation and moderated mediation models among a sample of 322 low-income, Mexican American mother-child dyads. Contrary to hypotheses and existing literature, concentrated disadvantage and residential instability were not predictive of maternal or child mental health outcomes. The percentage of residents identifying as Hispanic/Latino emerged as a protective neighborhood factor for both mothers and children. The neighborhood ethnocultural context may be especially relevant to understanding pathways of mental health specific to Mexican American families. More research is needed to understand specific parental and familial mechanisms underlying this protective effect.