California has the largest multilingual learner student population across the nation, the majority of whom identify as Latinx and speak Spanish at home. Considering the need to better support burgeoning Latinx and multilingual student populations and in recognition of the multifaceted benefits of bilingualism, biliteracy, and multiculturalism, California aims to quickly expand dual language immersion (DLI) programs, which requires further development and dissemination of data regarding the multidimensional advantages of DLI. Research has highlighted numerous positive student-level outcomes of two-way Spanish-English DLI programs. Additionally, limited but promising research on family- and parent-level outcomes associated with DLI calls for further examination of parent behaviors that may be occurring in conjunction with child DLI participation. Given the significant positive association between parent engagement (PE) and children’s social-emotional and academic outcomes, parents’ generally positive perceptions of DLI, and the potential for DLI programs to reduce linguistic and cultural barriers to PE that pervade English-only education, strengthened PE ought to be evaluated as a potential key outcome associated with DLI. Grounded in a transactional ecological theoretical understanding of the potential for school-based programs to broadly impact students and families across contexts, the present study explored PE in relation to Spanish-English DLI. Specifically, this study introduced a conceptualization of PE as a positive familial outcome associated with student DLI participation, rather than solely focusing on PE as a contributor to student success, thereby bolstering data on possible benefits of DLI for families. This study utilized a convergent parallel mixed methods design to explore the potential impact of DLI on PE among California elementary school parents. The researcher utilized the novel Culturally Sensitive Parent Engagement Questionnaire (CSPEQ; Scheller, 2022) to collect PE data among parents in two participating elementary schools. The researcher also ran semi-structured focus groups with DLI parents from the same two schools to explore parents’ perceived impact of DLI on PE across contexts. Multiple linear regression analyses demonstrated marginally increased PE scores for parents of children in DLI compared to parents of children in English-only programs but no statistically significant impact of child DLI participation on PE. However, thematic analysis of focus group responses primarily highlighted parents’ perceived strengthened PE across home, school, community, familial, and social contexts in association with DLI participation. Taken together, findings from the present study illuminate PE as a potential positive outcome of DLI and support the need for further investigation of the relationship between child DLI participation and culturally responsive PE behaviors. Broadly, this study’s findings shed light on the potential mechanisms and various dimensions through which DLI may strengthen parents’ engagement with their children’s education, learning, and positive development overall.