What can psychologists do to address social determinants of health and promote health equity among America's approximately 20 million children in immigrant families (CIF)? This article identifies gaps in current research and argues for a stronger role for psychologists. Psychologists can advocate for and enact changes in institutional systems that contribute to inequities in social determinants of health and promote resources and services necessary for CIF to flourish. We consider systemic exclusionary and discriminatory barriers faced by CIF, including a heightened anti-immigrant political climate, continued threat of immigration enforcement, restricted access to the social safety net, and the disproportionate health, economic, and educational burden of the COVID-19 pandemic. We highlight the potential role of psychologists in (a) leading prevention that addresses stressors such as poverty and trauma; (b) changing systems to mitigate risk factors for CIF; (c) expanding workforce development across multiple disciplines to better serve their needs; (d) identifying mechanisms, such as racial profiling, that contribute to health inequity, and viewing them as public health harms; and (e) guiding advocacy for resources at local, state, and federal levels, including by linking discriminatory policies or practices with health inequity. A key recommendation to increase psychologists' impact is for academic and professional institutions to strengthen relationships with policymakers to effectively convey these findings in spaces where decisions about policies and practices are made. We conclude that psychologists are well positioned to promote systemic change across multiple societal levels and disciplines to improve the well-being of CIF and offer them a better future.