Although people other than mothers participate in feeding, few interventions include non-maternal caregivers, especially those promoting healthy development among children aged 0-3 years. Understanding the role and influence of non-maternal caregivers is essential for the development and effectiveness of early childhood feeding interventions; yet, no reviews have examined non-maternal caregivers of children aged 0-3 years. This study assessed what is known about non-maternal caregivers' feeding of children aged 0-3. We systematically reviewed 38 empirical quantitative, qualitative, and mixed methods studies, cataloged in PubMed and Web of Science and published between 1/2000-6/2021. The studies showed that non-maternal caregivers engage in child feeding and their attitudes and behaviors affect child outcomes. Like mothers, non-maternal caregivers vary in the extent to which their knowledge and attitudes support recommended feeding practices and the extent to which they exhibit responsive feeding styles and practices. Children of broad ages were included in the studies; future research should include infant/toddler-only samples to allow for better assessment of age-specific feeding constructs. The studies also revealed issues specific to non-maternal caregivers that are unlikely to be addressed in interventions developed for mothers. Thus, the review highlighted features of non-maternal caregiving of children 0-3 years that could be addressed to support feeding and child outcomes.