As millions of children continue to live without parental care in under-resourced societies in low- and middle-income countries (LMICs), it is important for policymakers and practitioners to understand the specific characteristics within different care settings and the extent to which they are associated with outcomes of orphan and separated children (OSC). This study was designed to (1) examine if the psychosocial well-being of OSC in under-resourced societies in LMICs is more dependent on the availability of certain components of quality of care rather than the care setting itself (i.e. the residential care-based or community family-based setting), and (2) identify the relative significance of certain components of quality of care that are associated with a child's psychosocial well-being across different OSC care settings. This study drew from 36-month follow-up data from the Positive Outcomes for Orphans (POFO) Study and used a sample population of 2,013 (923 institution- and 1,090 community-based) OSC among six diverse study sites across five LMICs: Cambodia, India (Hyderabad and Nagaland), Kenya, Tanzania, and Ethiopia. Analyses showed that all four components of quality of care significantly predicted child psychosocial well-being. Child psychosocial well-being across "high" and "low" levels of quality of care showed negligible differences between residential- and community-based care settings, suggesting the important factor in child well-being is quality of care rather than setting of care. Practical and policy implications and future research are discussed.