Primary health care (PHC) is fundamental to achieving universal health coverage and health equity, yet building sustainable PHC systems remains a global challenge. This commentary compares the contrasting yet complementary experiences of Brazil and China along four analytical dimensions: community embeddedness, financial protection and sustainability, continuity of care and coordination across levels, digital support and its dual equity effect. Brazil's Family Health Strategy (FHS), rooted in community-based multidisciplinary teams and a rights-based framework, has significantly reduced mortality from preventable conditions and expanded access for marginalized populations, but faces sustainability threats from underfunding and political instability. China, by contrast, has adopted a state-driven, technologically enabled approach, leveraging telemedicine, electronic records, and AI-enabled tools to scale up PHC. Despite impressive coverage and financial protection, China struggles with limited public trust in frontline providers, fragmented care continuity, and a notable dual pattern in digital health: telemedicine has helped narrow the rural-urban gap, while the gap between younger and older users has widened. Drawing on recent policy documents and empirical studies, we distinguish broadly transferable principles from resource-intensive pathways, offering low- and middle-income country (LMIC) policymakers an integrative framework that prioritizes human-centered relational care reinforced by context-appropriate digital tools, predictable financing, and strong referral linkages within an equity-focused PHC foundation.