This meta-analysis reviews 126 empirical articles published over the past 50 years, examining the association between marital relationship quality and physical health in over 72,000 individuals. The study includes both clinical and surrogate health outcomes, such as mortality, cardiovascular reactivity, and biological markers like blood pressure. Greater marital quality is associated with better health, with mean effect sizes ranging from r = .07 to .21. These effects are similar in magnitude to those found between health behaviors and health outcomes. The analysis also explores the impact of confounding factors like age and socioeconomic status, as well as gender differences. However, the findings are limited by small sample sizes, unexplained heterogeneity, and designs that may not fully capture causal relationships. The study highlights the need for further research to explicitly test affective, health behavior, and biological mechanisms, and to focus on moderating factors that may influence the relationship between marital quality and health.This meta-analysis reviews 126 empirical articles published over the past 50 years, examining the association between marital relationship quality and physical health in over 72,000 individuals. The study includes both clinical and surrogate health outcomes, such as mortality, cardiovascular reactivity, and biological markers like blood pressure. Greater marital quality is associated with better health, with mean effect sizes ranging from r = .07 to .21. These effects are similar in magnitude to those found between health behaviors and health outcomes. The analysis also explores the impact of confounding factors like age and socioeconomic status, as well as gender differences. However, the findings are limited by small sample sizes, unexplained heterogeneity, and designs that may not fully capture causal relationships. The study highlights the need for further research to explicitly test affective, health behavior, and biological mechanisms, and to focus on moderating factors that may influence the relationship between marital quality and health.