Parenting self-efficacy has been shown to influence parenting practices and children’s developmental outcomes. However, little is known about how cultural orientation and parenting stress shape parenting self-efficacy and parenting practices, and how parenting self-efficacy and parenting practices uniquely shape children’s socio-emotional development in low-income, immigrant families. In a sample of 88 Mexican American (MA) and Chinese American (CA) low-income, immigrant mothers and their preschoolers, the present study examined the concurrent associations among mothers’ cultural orientation, parenting stress, parenting self-efficacy, parenting practices, and children’s socio-emotional adjustment. All constructs were measured by mothers’ self-reports. First, I examined how family demographic characteristics (family income, mothers’ education, mothers’ years in the US), mothers’ cultural orientation to heritage and American culture, and parenting stress (parental distress and parent-child dysfunctional interactions) were associated with mothers’ parenting self-efficacy. Results indicated that mothers’ heritage and American cultural orientations were both associated with greater parenting self-efficacy. In contrast, parenting stress—specifically, dysfunctional parent-child interaction—was associated with less parenting self-efficacy. Second, I examined the associations between parenting self-efficacy and parenting practices (authoritative and authoritarian parenting). Mothers’ parenting self-efficacy was uniquely associated with greater authoritative parenting. In addition, parenting self-efficacy mediated the associations between a) mother’s heritage cultural orientation, American cultural orientation, and parent-child dysfunctional interaction, and b) mothers’ authoritative parenting. Third, I examined how parenting self-efficacy was uniquely associated with children’s socio-emotional adjustment. Parenting self-efficacy was associated with more prosocial behaviors and less externalizing problems. Furthermore, authoritative parenting mediated the association between parenting self-efficacy and children’s prosocial behaviors. Last, I explored potential differences between cultural groups. Results indicated that MA mothers reported greater parenting self-efficacy compared to CA mothers. I also found cultural group differences in correlations among variables. Overall, the findings highlight the benefits of parenting self-efficacy for children’s socio-emotional adjustment and the complex contextual factors that shape parenting self-efficacy in immigrant families. Implications of findings for the development of parenting interventions for low-income immigrant families are discussed.