Biliteracy, the proficient ability to read and write in two languages integrating linguistic and cultural systems, is vital for preschool bilingual children’s lifelong learning and social adaptation in today’s interconnected world. This article examines biliteracy development in preschool bilingual children, focusing on the critical roles of vocabulary acquisition and oral narrative abilities as foundational to academic and cognitive growth. It identifies challenges like subtractive bilingualism, limited resources, biased assessments, and inadequate teacher training. This article proposes evidence-based interventions such as dual language programs, translanguaging practices, culturally responsive pedagogy, family engagement, and comprehensive assessments. By integrating linguistic and cultural systems, these strategies aim to support children’s biliteracy, fostering cognitive flexibility, cultural identity, and long-term success in multilingual contexts. The discussion provides practical insights for educators, policymakers, and parents to effectively nurture biliteracy from an early age.