As the U.S. population who speaks a language other than English at home continues to grow, few studies have focused on the effect of parental beliefs on the importance of bilingualism have on language outcomes of their children. In this study, we surveyed families raising Spanish-English bilingual children on their beliefs concerning both languages, language practices they implement at home, at school, and in the community, and language outcomes of their children. Using a single mediator model, this study aimed to understand the impact of parental beliefs on language outcomes in Spanish and English and the mediating effects of language practices. We then examined the individual mediating effects of language practices at home, school, and community on the relationship between parental beliefs and language outcomes for each language using a multiple mediator model. Our results suggest that parental beliefs in Spanish predict Spanish language outcomes and parental beliefs in English predict English outcomes and that practices in each language mediated this effect. In particular, we found that Spanish practices at home mediated the effect of language outcomes in Spanish and that English practices at home and in the community mediated English language outcomes.