For children with chronic conditions, well-being is closely related to how well their families function. Most prior research syntheses on family functioning and child well-being have focused on children with a single condition, thereby limiting the potential to aggregate and build on what is known across conditions. To address this challenge, research reports were reviewed and meta-analyses conducted of findings on the relationship between family functioning and child well-being across a range of chronic physical conditions. The sample was derived from a larger systematic review study that included 1,028 reports published between January 1, 2000 and March 31, 2014. The current review includes 53 studies in which a relationship between family functioning and child well-being was analyzed using one of four family measures: Family Adaptability and Cohesion Evaluation Scales, Family Environment Scale, Family Relationship Index, or Family Assessment Device. Most studies were cross-sectional and observational (n = 43, 81%). The most frequently studied conditions were diabetes, cancer, sickle cell disease, and asthma. In 37 studies, findings were sufficiently comparable to conduct meta-analyses. Significant correlations were identified between children's psychological health and seven of nine dimensions of family functioning. Significant correlations also were found between dimensions of family functioning and children's problem behaviors, social competence, quality of life, and, to a lesser extent, adherence and physical health. Of the family dimensions, cohesion and conflict were associated most strongly with child outcomes. Understanding the specific family variables, such as conflict, linked to varied child outcomes is key for intervention development. © 2016 Wiley Periodicals, Inc.