<p>The study adopts the Social Ecology Model to measure left-behind children’s well-being and examines the microsystem context, which most significantly influences left-behind children’s well-being. For the study, a multistage random sampling technique was used to choose four hundred eighty left-behind children aged 10 to 16 in Sichuan province, China to participate in the study. The results from the study indicate that left-behind children present a positive and significant relationship with the microsystem context, and the family context has the most significant influence on children’s material, psychological, social well-being, and overall well-being, and the neigbourhood context has the most significant influence on children’s physical and educational well-being. The study recommends that the government improve social expenditure on children’s family benefits and family and neighbourhood services, and provide social services to promote family and neighbourhood contexts and to safeguard left-behind children’s well-being. </p>